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1.
J Strength Cond Res ; 2024 Jan 19.
Article in English | MEDLINE | ID: mdl-38039426

ABSTRACT

ABSTRACT: Chen, C-F, Chuang, C-Y, Wang, C-C, Liu, S-A, Chang, H-W, and Chan, K-H. Lower repetition induces similar postactivation performance enhancement to repetition maximum after a single set of heavy-resistance exercise. J Strength Cond Res XX(X): 000-000, 2023-The study was divided into 2 parts to investigate the acute postactivation performance enhancement (PAPE) responses to lower repetitions at the same load of 87% 1 repetition maximum (1RM) in the upper and lower body. In part 1, 14 athletes performed plyometric push-up (PPU) after the conditioning activity (CA) of bench press (BP). In part 2, 13 athletes performed a countermovement jump (CMJ) after the CA of parallel squat (PS). Subjects completed 3, 4, or 5 repetitions (trials CA-3, CA-4, or CA-5) of BP or PS in randomized and counterbalanced order. The velocity of each movement of the trial was recorded. The PPU or CMJ was tested every 2 minutes after the trial up to 12 minutes to assess the Post-Max and optimal individual PAPE time. The mean velocity of the last movement of BP in CA-5 was significantly lower than that in CA-3 (0.23 ± 0.06 vs. 0.28 ± 0.06 m·second -1 , p < 0.05), and the velocity of PS in CA-4 or CA-5 was significantly lower than that in CA-3 (0.53 ± 0.07 and 0.50 ± 0.05 vs. 0.57 ± 0.07 m·second -1 , p < 0.05). The peak force of PPU and jump height of CMJ at Post-Max in the 3 trials were significantly greater than those at Pre ( p < 0.05). There were no significant differences among trials in the optimal individual PAPE times in either part of the study. A single set of 87% 1RM resistance exercises with 3 or 4 repetitions in both the upper body and the lower body induces similar PAPE to repetition maximum.

2.
Article in English | MEDLINE | ID: mdl-37607137

ABSTRACT

Assessing the condition of every schizophrenia patient correctly normally requires lengthy and frequent interviews with professionally trained doctors. To alleviate the time and manual burden on those mental health professionals, this paper proposes a multimodal assessment model that predicts the severity level of each symptom defined in Scale for the Assessment of Thought, Language, and Communication (TLC) and Positive and Negative Syndrome Scale (PANSS) based on the patient's linguistic, acoustic, and visual behavior. The proposed deep-learning model consists of a multimodal fusion framework and four unimodal transformer-based backbone networks. The second-stage pre-training is introduced to make each off-the-shelf pre-trained model learn the pattern of schizophrenia data more effectively. It learns to extract the desired features from the view of its modality. Next, the pre-trained parameters are frozen, and the light-weight trainable unimodal modules are inserted and fine-tuned to keep the number of parameters low while maintaining the superb performance simultaneously. Finally, the four adapted unimodal modules are fused into a final multimodal assessment model through the proposed multimodal fusion framework. For the purpose of validation, we train and evaluate the proposed model on schizophrenia patients recruited from National Taiwan University Hospital, whose performance achieves 0.534/0.685 in MAE/MSE, outperforming the related works in the literature. Through the experimental results and ablation studies, as well as the comparison with other related multimodal assessment works, our approach not only demonstrates the superiority of our performance but also the effectiveness of our approach to extract and integrate information from multiple modalities.


Subject(s)
Cues , Schizophrenia , Humans , Schizophrenia/diagnosis , Linguistics , Learning , Acoustics
3.
Biology (Basel) ; 11(8)2022 Jul 29.
Article in English | MEDLINE | ID: mdl-36009767

ABSTRACT

The purpose of this study was to investigate the effects of 6-week betaine supplementation during a preparatory period of collegiate athletes on muscular power and strength. Sixteen male collegiate athletes received 5 g/day of betaine (betaine group, n = 9) or carboxymethyl cellulose (placebo group, n = 7) for 6 weeks. All participants engaged in their regular training during the experimental period. The overhead medicine-ball throw (OMBT), countermovement jump, and maximal strength (one repetition maximum, 1-RM) on the bench press, overhead press, half squat, and sumo dead lift by the participants were assessed before and after betaine supplementation. Blood lipids were also analyzed before and after betaine supplementation. After supplementation, there were no significant differences between betaine and placebo groups on any variables. Compared to presupplementation, the performance of OMBT and 1-RM of overhead press and half squat in the betaine group had significantly improved (p < 0.05). By contrast, no significant differences were observed in the placebo group before and after supplementation. Blood analysis revealed no negative effect on blood lipid profiles. Betaine seems to be a useful nutritional strategy to improve and maintain performance during 6-week preparatory periods in collegiate athletes.

4.
IEEE J Biomed Health Inform ; 26(11): 5704-5715, 2022 11.
Article in English | MEDLINE | ID: mdl-35976843

ABSTRACT

Schizophrenia is a mental disorder that will progressively change a person's mental state and cause serious social problems. Symptoms of schizophrenia are highly correlated to emotional status, especially depression. We are thus motivated to design a mental status detection system for schizophrenia patients in order to provide an assessment tool for mental health professionals. Our system consists of two phases, including model learning and status detection. For the learning phase, we propose a multi-task learning framework to infer the patient's mental state, including emotion and depression severity. Unlike previous studies inferring emotional status mainly by facial analysis, in the learning phase, we adopted a Cross-Modality Graph Convolutional Network (CMGCN) to effectively integrate visual features from different modalities, including the face and context. We also designed task-aware objective functions to realize better model convergence for multi-task learning, i.e., emotion recognition and depression estimation. Further, we followed the correlation between depression and emotion to design the Emotion Passer module, to transfer the prior knowledge on emotion to the depression model. For the detection phase, we drew on characteristics of schizophrenia to detect the mental status. In the experiments, we performed a series of experiments on several benchmark datasets, and the results show that the proposed learning framework boosts state-of-the-art (SOTA) methods significantly. In addition, we take a trial on schizophrenia patients, and our system can achieve 69.52 in mAP in a real situation.


Subject(s)
Schizophrenia , Humans , Schizophrenia/diagnosis , Facial Expression , Emotions , Visual Perception
5.
Arterioscler Thromb Vasc Biol ; 39(10): 2157-2167, 2019 10.
Article in English | MEDLINE | ID: mdl-31462093

ABSTRACT

OBJECTIVE: Although the clinical and biological importance of calcification is well recognized for the extracerebral vasculature, its role in cerebral vascular disease, particularly, intracranial aneurysms (IAs), remains poorly understood. Extracerebrally, 2 distinct mechanisms drive calcification, a nonatherosclerotic, rapid mineralization in the media and a slower, inflammation driven, atherosclerotic mechanism in the intima. This study aims to determine the prevalence, distribution, and type (atherosclerotic, nonatherosclerotic) of calcification in IAs and assess differences in occurrence between ruptured and unruptured IAs. Approach and Results: Sixty-five 65 IA specimens (48 unruptured, 17 ruptured) were resected perioperatively. Calcification and lipid pools were analyzed nondestructively in intact samples using high resolution (0.35 µm) microcomputed tomography. Calcification is highly prevalent (78%) appearing as micro (<500 µm), meso (500 µm-1 mm), and macro (>1 mm) calcifications. Calcification manifests in IAs as both nonatherosclerotic (calcification distinct from lipid pools) and atherosclerotic (calcification in the presence of lipid pools) with 3 wall types: Type I-only calcification, no lipid pools (20/51, 39%), Type II-calcification and lipid pools, not colocalized (19/51, 37%), Type III-calcification colocalized with lipid pools (12/51, 24%). Ruptured IAs either had no calcifications or had nonatherosclerotic micro- or meso-calcifications (Type I or II), without macro-calcifications. CONCLUSIONS: Calcification in IAs is substantially more prevalent than previously reported and presents as both nonatherosclerotic and atherosclerotic types. Notably, ruptured aneurysms had only nonatherosclerotic calcification, had significantly lower calcification fraction, and did not contain macrocalcifications. Improved understanding of the role of calcification in IA pathology should lead to new therapeutic targets.


Subject(s)
Aneurysm, Ruptured/pathology , Atherosclerosis/pathology , Calcinosis/pathology , Image Processing, Computer-Assisted/methods , Intracranial Aneurysm/pathology , X-Ray Microtomography/methods , Aged , Analysis of Variance , Atherosclerosis/diagnostic imaging , Calcinosis/diagnostic imaging , Calcinosis/epidemiology , Humans , Intracranial Aneurysm/surgery , Middle Aged , Prevalence , Risk Assessment , Sampling Studies , Severity of Illness Index , Statistics, Nonparametric , Tissue and Organ Harvesting
6.
Curr Protoc Cytom ; 87(1): e51, 2019 01.
Article in English | MEDLINE | ID: mdl-30379412

ABSTRACT

Multiphoton-induced second-harmonic generation and two-photon excitation enable imaging of collagen and elastin fibers at micron-level resolution to depths of hundreds of microns, without the use of exogenous stains. These attributes can be leveraged for quantitative analysis of the 3D architecture of collagen and elastin fibers within intact, soft tissue specimens such as the artery and bladder wall. This architecture influences the function of intramural cells and also plays a primary role in determining tissue passive mechanical properties. Calcification deposition in soft tissues is a highly prevalent pathology in both older and diseased populations that can alter tissue properties. In this unit, we provide a protocol for simultaneous multiphoton microscopy (MPM) imaging and analysis of 3D collagen and elastin structures with calcification, which is effective for fixed and fresh intact samples. We also provide an associated micro-CT protocol to identify regions of interest in the samples as a means to target the MPM imaging. © 2018 by John Wiley & Sons, Inc.


Subject(s)
Calcification, Physiologic , Collagen/chemistry , Elastin/chemistry , Imaging, Three-Dimensional , Microscopy, Fluorescence, Multiphoton/methods , Organ Specificity , Animals , Humans , X-Ray Microtomography
7.
Sensors (Basel) ; 17(2)2017 Feb 03.
Article in English | MEDLINE | ID: mdl-28165365

ABSTRACT

This paper introduces an alternative approach to the camber angle measurement for vehicle wheel alignment. Instead of current commercial approaches that apply computation vision techniques, this study aims at realizing a micro-control-unit (MCU)-based camber inspection system with a 3-axis accelerometer. We analyze the precision of the inspection system for the axis misalignments of the accelerometer. The results show that the axes of the accelerometer can be aligned to the axes of the camber inspection system imperfectly. The calibrations that can amend these axis misalignments between the camber inspection system and the accelerometer are also originally proposed since misalignments will usually happen in fabrications of the inspection systems. During camber angle measurements, the x-axis or z-axis of the camber inspection system and the wheel need not be perfectly aligned in the proposed approach. We accomplished two typical authentic camber angle measurements. The results show that the proposed approach is applicable with a precision of ± 0.015 ∘ and therefore facilitates the camber measurement process without downgrading the precision by employing an appropriate 3-axis accelerometer. In addition, the measured results of camber angles can be transmitted via the medium such as RS232, Bluetooth, and Wi-Fi.

8.
Soft Matter ; 10(44): 8829-37, 2014 Nov 28.
Article in English | MEDLINE | ID: mdl-25284029

ABSTRACT

A variety of cell types exhibit phenotype changes in response to the mechanical stiffness of the substrate. Many cells excluding neurons display an increase in the spread area, actin stress fiber formation and larger focal adhesion complexes as substrate stiffness increases in a sparsely populated culture. Cell proliferation is also known to directly correlate with these phenotype changes/changes in substrate stiffness. Augmented spreading and proliferation on stiffer substrates require nuclear transcriptional regulator YAP (Yes associated protein) localization in the cell nucleus and is tightly coupled to larger traction force generation. In this study, we show that different types of fibroblasts can exhibit spread morphology, well defined actin stress fibers, and larger focal adhesions even on very soft collagen gels (modulus in hundreds of Pascals) as if they are on hard glass substrates (modulus in GPa, several orders of magnitude higher). Strikingly, we show, for the first time, that augmented spreading and other hard substrate cytoskeleton architectures on soft collagen gels are not correlated with the cell proliferation pattern and do not require YAP localization in the cell nucleus. Finally, we examine the response of human colon carcinoma (HCT-8) cells on soft collagen gels. Recent studies show that human colon carcinoma (HCT-8) cells form multicellular clusters by 2-3 days when cultured on soft polyacrylamide (PA) gels with a wide range of stiffness (0.5-50 kPa) and coated with an extracellular matrix, ECM (collagen monomer/fibronectin). These clusters show limited spreading/wetting on PA gels, form 3D structures at the edges, and eventually display a remarkable, dissociative metastasis like phenotype (MLP), i.e., epithelial to rounded morphological transition after a week of culture on PA gels only, but not on collagen monomer coated stiff polystyrene/glass where they exhibit enhanced wetting and form confluent monolayers. Here, we show that HCT-8 cell clusters also show augmented spreading/wetting on soft collagen gels and eventually form confluent monolayers as on rigid glass substrates and MLP is completely inhibited on soft collagen gels. Overall, these results suggest that cell-material interactions (soft collagen gels in this case) can induce cellular phenotype and cytoskeleton organization in a remarkably distinct manner compared to a classical synthetic polyacrylamide (PA) hydrogel cell culture model and may contribute in designing new functional biomaterials.


Subject(s)
Cellular Reprogramming , Collagen/pharmacology , Gels/pharmacology , Phenotype , 3T3 Cells , Animals , Cell Adhesion , Cell Line, Tumor , Cell Proliferation , Collagen/chemistry , Elastic Modulus , Fibroblasts/cytology , Fibroblasts/drug effects , Fibroblasts/physiology , Fibronectins/pharmacology , Gels/chemistry , Humans , Mice , Stress Fibers/metabolism
9.
J Altern Complement Med ; 17(9): 843-9, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21854198

ABSTRACT

OBJECTIVES: In Traditional Chinese Medicine (TCM), Qi maintains the physiologic function and indicates physiologic energy. Glucose provides energy to humans, thereby playing a role analogous to "nutritive Qi." This study aims to identify the correlations among blood glucose, Qi Vacuity (QV), and the electrical conductances of acupoints. METHODS: Twenty (20) subjects who had ingested a glucose solution after a 10-hour overnight fast were divided into two groups based on QV score. Then their acupoint conductances were measured sequentially using a Ryodoraku instrument during the following 120 minutes. Data were analyzed using generalized estimating equations as a time-series model. RESULTS: Eight (8) subjects were categorized into a Qi Vacuous group for QV score >6, and the other 12 subjects were categorized into a Qi non-Vacuous group for QV score ≤6. During the first 30 minutes, the acupoint conductances decreased on the left Pericardium, left Heart, right Liver, Kidney, and Gallbladder meridians in the Qi Vacuous group, and increased on the right Pericardium meridian and decreased on the right Gallbladder meridian in the Qi non-Vacuous group. From 30 to 60 and 60 to 90 minutes, the acupoint conductances decreased on the Gallbladder, Heart, left Pericardium, left Kidney, right Liver, and right Stomach meridians in the Qi Vacuous group, and increased on the Pericardium, Heart, left Small Intestine, and left Lung meridians in the Qi non-Vacuous group. During the last 30 minutes, more of the acupoint conductances were increased in the Qi non-Vacuous group, whereas only the acupoint conductance on the liver meridian was increased and that on the left gallbladder meridian was decreased in the Qi Vacuous group. CONCLUSIONS: The findings suggest that the energy distribution and transformation in meridian vessels present different patterns in QV and non-QV groups after glucose consumption.


Subject(s)
Acupuncture Points , Electric Conductivity , Glucose/pharmacology , Meridians , Qi , Adult , Blood Glucose/metabolism , Female , Humans , Male , Medicine, Chinese Traditional , Young Adult
10.
Integr Cancer Ther ; 10(4): 312-6, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21382955

ABSTRACT

Anthracyclines are potent antineoplastic agents associated with cardiotoxicity, which may lead to congestive heart failure, causing impairment of autonomic cardiovascular function as assessed by heart rate variability (HRV). This decreases survival rates. This study aimed to determine whether music therapy intervention improves autonomic function in anthracycline-treated breast cancer patients, and if so, whether such improvements persist after cessation of the intervention. Participants were 12 women with breast cancer who had undergone mastectomy or breast-conserving treatment and adjuvant chemotherapy; they attended 8 weekly music therapy sessions, each lasting 2 hours. Electrocardiogram traces (5 minutes) for HRV analysis were recorded 4 times: prior to the first music session, T1; after the fourth music session, T2; after the eighth music session, T3; and 4 weeks after the completion of music therapy, T4. HRV parameters were subjected to a nonparametric Friedman test on the differences between T1 and T2, T3, and T4. The standard deviation of normal intervals and the total power of HRV parameters, related to global autonomic function, were significantly higher at T3 than at T1. The root-mean-square differences of successive normal R-R intervals and high-frequency (HF) HRV parameters, related to parasympathetic activity, were significantly increased, but no change was seen in the LF/HF ratio of HRV parameters (which is related to sympathetic activity) during the music therapy. Global autonomic function and parasympathetic activity had not changed significantly at T4 relative to T1. The authors provide preliminary evidence of the benefits of music therapy for anthracycline-treated breast cancer survivors.


Subject(s)
Antibiotics, Antineoplastic/adverse effects , Autonomic Nervous System/physiopathology , Breast Neoplasms/drug therapy , Doxorubicin/adverse effects , Heart Diseases/therapy , Music Therapy , Adult , Antibiotics, Antineoplastic/therapeutic use , Autonomic Nervous System/drug effects , Breast Neoplasms/physiopathology , Cardiotoxins/adverse effects , Cardiotoxins/therapeutic use , Doxorubicin/therapeutic use , Electrocardiography , Female , Heart Diseases/chemically induced , Heart Rate , Humans , Middle Aged
11.
Sleep Breath ; 15(3): 317-23, 2011 Sep.
Article in English | MEDLINE | ID: mdl-20602177

ABSTRACT

STUDY OBJECTIVES: Obstructive sleep apnea (OSA) is a major concern in modern medicine; however, it is difficult to diagnose. Screening questionnaires such as the Berlin questionnaire, Rome questionnaire, and BASH'IM score are used to identify patients with OSA. However, the sensitivity and specificity of these tools are not satisfactory. We aim to introduce an artificial intelligence method to screen moderate to severe OSA patients (apnea-hypopnea index ≧15). PATIENTS AND METHODS: One hundred twenty patients were asked to complete a newly developed questionnaire before undergoing an overnight polysomnography (PSG) study. One hundred ten validated questionnaires were enrolled in this study. Genetic algorithm (GA) was used to build the five best models based on these questionnaires. The same data were analyzed with logistic regression (LR) for comparison. RESULTS: The sensitivity of the GA models varied from 81.8% to 88.0%, with a specificity of 95% to 97%. On the other hand, the sensitivity and specificity of the LR model were 55.6% and 57.9%, respectively. CONCLUSIONS: GA provides a good solution to build models for screening moderate to severe OSA patients, who require PSG evaluation and medical intervention. The questionnaire did not require any special biochemistry data and was easily self-administered. The sensitivity and specificity of the GA models are satisfactory and may improve when more patients are recruited.


Subject(s)
Artificial Intelligence , Diagnosis, Computer-Assisted , Mass Screening/methods , Neural Networks, Computer , Polysomnography , Sleep Apnea, Obstructive/diagnosis , Surveys and Questionnaires , Adult , Algorithms , Comorbidity , Female , Humans , Male , Middle Aged , Risk Factors , Sensitivity and Specificity , Taiwan
12.
Complement Ther Med ; 18(5): 224-6, 2010 Oct.
Article in English | MEDLINE | ID: mdl-21056846

ABSTRACT

OBJECTIVE: Data on the effects of music therapy on subjective sensations and the physiological parameters of heart rate variability (HRV) in treated cancer survivors are scarce. The aim of this study was to determine whether or not music therapy affects the sensations of fatigue, comfort, and relaxation in cancer survivors, and affects the activities of the sympathetic and parasympathetic nervous systems as indicated by HRV parameters. METHODS: Twenty-three patients aged 30-67 years and with cancer that had been treated at least 6 months previously received music therapy for about 2h, which included singing, listening to music, learning the recorder, and performing music. Subjective sensations and electrocardiogram were recorded before and after the music therapy. The low-frequency and high-frequency components of HRV were assessed by the frequency analysis of sequential R wave to R wave intervals of electrocardiogram obtained from 5-min recordings. Subjective sensations were quantitatively assessed using a visual analog mood scale. RESULTS: Two hours of music therapy significantly increased relaxation sensations and significantly decreased fatigue sensation in treated cancer survivors. Moreover, the HRV parameters showed that parasympathetic nervous system activity increased and sympathetic nervous system activity decreased. CONCLUSION: This study provides preliminary evidence that music therapy may be clinically useful for promoting relaxation sensation and increasing parasympathetic nervous system activity in treated cancer survivors.


Subject(s)
Fatigue , Heart Rate/physiology , Music Therapy , Neoplasms/physiopathology , Parasympathetic Nervous System/physiology , Sympathetic Nervous System/physiology , Adult , Affect , Aged , Electrocardiography , Female , Humans , Male , Middle Aged , Neoplasms/therapy , Pain Measurement , Pilot Projects , Relaxation , Sensation
13.
J Med Chem ; 50(21): 5202-16, 2007 Oct 18.
Article in English | MEDLINE | ID: mdl-17887659

ABSTRACT

The peptide hormone ghrelin is the endogenous ligand for the type 1a growth hormone secretagogue receptor (GHS-R1a) and the only currently known circulating appetite stimulant. GHS-R1a antagonism has therefore been proposed as a potential approach for obesity treatment. More recently, ghrelin has been recognized to also play a role in controlling glucose-induced insulin secretion, which suggests another possible benefit for a GHS-R1a antagonist, namely, the role as an insulin secretagogue with potential value for diabetes treatment. In our laboratories, piperidine-substituted quinazolinone derivatives were identified as a new class of small-molecule GHS-R1a antagonists. Starting from an agonist with poor oral bioavailability, optimization led to potent, selective, and orally bioavailable antagonists. In vivo efficacy evaluation of selected compounds revealed suppression of food intake and body weight reduction as well as glucose-lowering effects mediated by glucose-dependent insulin secretion.


Subject(s)
Diabetes Mellitus/drug therapy , Obesity/drug therapy , Quinazolinones/chemical synthesis , Receptors, Ghrelin/antagonists & inhibitors , Administration, Oral , Animals , Binding, Competitive , Blood Glucose/analysis , Cell Line , Eating/drug effects , Glucose Tolerance Test , Humans , Male , Mice , Mice, Inbred C57BL , Quinazolinones/chemistry , Quinazolinones/pharmacology , Radioligand Assay , Rats , Rats, Wistar , Stereoisomerism , Structure-Activity Relationship , Weight Loss/drug effects
15.
Bioorg Med Chem Lett ; 17(15): 4378-81, 2007 Aug 01.
Article in English | MEDLINE | ID: mdl-17574417

ABSTRACT

Novel anthranilamides were surprisingly found to exert additional activity on B-RAF. Corresponding thiophene, pyrazole, and thiazole core analogs were prepared as VEGFR-2 inhibitors with c-KIT, and B-RAF activity. Compounds in the phenyl, thiophene, and thiazole series are in vivo active.


Subject(s)
Antineoplastic Agents/pharmacology , Neoplasms/drug therapy , Protein Kinase Inhibitors/pharmacology , Vascular Endothelial Growth Factor Receptor-2/antagonists & inhibitors , Animals , Antineoplastic Agents/therapeutic use , Cell Line, Tumor , Humans , Mice , Protein Kinase Inhibitors/therapeutic use , Structure-Activity Relationship
16.
Chirality ; 14(2-3): 151-62, 2002.
Article in English | MEDLINE | ID: mdl-11835558

ABSTRACT

Regio- and enantioselectivity in the asymmetric aminohydroxylation (AA) reaction of O-substituted 4-hydroxy-2-butenoates as well as the mechanism of the reaction were studied. When the electronic properties of the phenyl group in a substrate were altered by using different substituents, two conflicting trends were observed: The O-benzoyl substrates showed greater regio- and enantioselectivity when an electron-donating substituent was attached at the C-4 position of the phenyl group, while the O-benzyl substrates exhibited better regio- and enantioselectivity with an electron-withdrawing substituent at the C-4 position of the phenyl moiety. Thus, these results have disclosed hitherto unknown remarkable electronic effects in the AA reaction. Detailed analysis of possible electronic interactions in the chiral catalyst-substrate complex has revealed the importance of dipolar aromatic-aromatic interactions between the aromatic substituent of the substrate and the nitrogen heteroaromatic moiety of the chiral ligand for effective regiocontrol as well as enantioface selection in the AA reaction. A plausible model of the key intermediate in the AA reaction of O-substituted 4-hydroxy-2-butenoates is proposed.


Subject(s)
Butyrates/chemical synthesis , Hydrogen-Ion Concentration , Amination , Catalysis , Chromatography, High Pressure Liquid , Hydroxylation , Indicators and Reagents , Ligands , Magnetic Resonance Spectroscopy , Models, Molecular , Spectrophotometry, Infrared , Stereoisomerism
17.
Inorg Chem ; 35(9): 2530-2537, 1996 Apr 24.
Article in English | MEDLINE | ID: mdl-11666466

ABSTRACT

Oxidative addition of diorganyl diselenides to the coordinatively unsaturated, low-valent transition-metal-carbonyl fragment [Mn(CO)(5)](-) produced cis-[Mn(CO)(4)(SeR)(2)](-). The complex cis-[PPN][Mn(CO)(4)(SePh)(2)] crystallized in triclinic space group P&onemacr; with a = 10.892(8) Å, b = 10.992(7) Å, c = 27.021(4) Å, alpha = 101.93(4) degrees, beta = 89.79(5) degrees, gamma = 116.94(5) degrees, V = 2807(3) Å(3), and Z = 2; final R = 0.085 and R(w) = 0.094. Thermolytic transformation of cis-[Mn(CO)(4)(SeMe)(2)](-) to [(CO)(3)Mn(&mgr;-SeMe)(3)Mn(CO)(3)](-) was accomplished in high yield in THF at room temperature. Crystal data for [Na-18-crown-6-ether][(CO)(3)Mn(&mgr;-SeMe)(3)Mn(CO)(3)]: trigonal space group R&thremacr;, a = 13.533(3) Å, c = 32.292(8) Å, V = 5122(2) Å(3), Z = 6, R = 0.042, R(w) = 0.041. Oxidation of Co(2+) to Co(3+) by diphenyl diselenide in the presence of chelating metallo ligands cis-[Mn(CO)(4)(SePh)(2)](-) and cis-[Mn(CO)(4)(TePh)(2)](-), followed by a bezenselenolate ligand rearranging to bridge two metals and a labile carbonyl shift from Mn to Co, led directly to [(CO)(4)Mn(&mgr;-TePh)(2)Co(CO)(&mgr;-SePh)(3)Mn(CO)(3)]. Crystal data: triclinic space group P&onemacr;, a = 11.712(3) Å, b = 12.197(3) Å, c = 15.754(3) Å, alpha = 83.56(2) degrees, beta = 76.13(2) degrees, gamma = 72.69(2) degrees, V = 2083.8(7) Å(3), Z = 2, R = 0.040, R(w) = 0.040. Addition of fac-[Fe(CO)(3)(SePh)(3)](-) to fac-[Mn(CO)(3)(CH(3)CN)(3)](+) resulted in formation of (CO)(3)Mn(&mgr;-SePh)(3)Fe(CO)(3). This neutral heterometallic complex crystallized in monoclinic space group P2(1)/n with a = 8.707(2) Å, b = 17.413(4) Å, c = 17.541(4) Å, beta = 99.72(2) degrees, V = 2621(1) Å(3), and Z = 4; final R = 0.033 and R(w) = 0.030.

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