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1.
Chemistry ; : e202401885, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977428

RESUMO

The understanding of supramolecular chirality in self-assembled molecular networks (SAMNs) on surfaces generates a lot of interest because of its relation to the production of chiral sensors, reactors, and catalysts. We herein report the adsorption of a prochiral solvent molecule in porous SAMNs formed by a chiral dehydrobenzo[12]annulene (cDBA) derivative. Through the prochirality recognition of a solvent molecule, the supramolecular chirality of the SAMN is switched: the cDBA exclusively forms a counter-clockwise pore through co-adsorption of the solvent molecule in prochiral 1,2,4-trichlorobenzene, while in 1-phenyloctane it produces the opposite chiral, clockwise pore. The prochirality recognition of the solvent molecule in the chiral SAMN pores is attributed to the adaptable conformational changes of the chiral chains of the cDBA molecule.

2.
J Endourol ; 38(6): 564-572, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38545752

RESUMO

Purpose: We herein describe the superficial preprostatic vein (SPV) anatomy and determine its relationship with the accessory pudendal artery (APA). Materials and Methods: We reviewed 500 patients with localized prostate cancer who underwent conventional robot-assisted radical prostatectomy between April 2019 and March 2023 at our institution. SPV was defined as "any vein coming from the space between the puboprostatic ligaments and running within the retropubic adipose tissue anterior to the prostate toward the vesical venous plexus or pelvic side wall." While APA was defined as "any artery located in the periprostatic region running parallel to the dorsal vascular complex and extending caudal toward the anterior perineum." The intraoperative anatomy of each SPV and APA was described. Results: SPVs had a prevalence rate of 88%. They were preserved in 252 men (58%) and classified as I-, reversed-Y (rY)-, Y-, or H-shaped (64%, 22%, 12%, and 2%, respectively) based on their intraoperative appearance. Overall, 214 APAs were found in 142 of the 252 men with preserved SPV (56%; 165 lateral and 50 apical APAs in 111 and 41 men, respectively). SPVs were pulsatile in 39% men perhaps due to an accompanying tiny artery functioning as a median APA. Pulsations seemed to be initially absent in most SPVs but become apparent late during surgery possibly due to increased arterial and venous blood flow after prostate removal. Pulsations were common in men with ≥1 APA. Conclusions: This study, which described the anatomical variations in arteries and veins around the prostrate and their preservation techniques, revealed that preserving this vasculature may help preserve postprostatectomy erection. ClinicalTrials: The Clinical Research Registration Number is 230523D.


Assuntos
Artérias , Próstata , Prostatectomia , Procedimentos Cirúrgicos Robóticos , Veias , Humanos , Masculino , Prostatectomia/métodos , Procedimentos Cirúrgicos Robóticos/métodos , Próstata/irrigação sanguínea , Próstata/cirurgia , Pessoa de Meia-Idade , Idoso , Artérias/anatomia & histologia , Veias/anatomia & histologia , Veias/cirurgia , Neoplasias da Próstata/cirurgia , Neoplasias da Próstata/patologia
3.
Percept Mot Skills ; 131(2): 348-362, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38281966

RESUMO

An adequate foot clearance height while stepping over an obstacle is important for safety in daily life. In the present study, we examined whether visual illusions affect foot clearance during a stepping-over action, and whether this is further influenced by gaze behavior. Twelve participants stepped over an obstacle placed four meters away under conditions of three different obstacle characteristics: white, horizontal, or vertical lines. We measured the participants' foot clearances during the step-over action and their gaze behavior during the approaching phase. Participants stepped significantly higher over the obstacles in the vertical lines (illusion) condition. The duration of gaze fixation on the obstacle positively correlated with increased foot clearance in the vertical condition, suggesting that the effect of the visual illusion on foot clearance was enhanced by prolonged gaze fixation. Conversely, prolonged fixation negatively correlated with foot clearance in the white (control) condition, implying that a cautious perception of an obstacle may contribute to efficient stepping-over action.


Assuntos
Ilusões , Humanos , Marcha , , Fixação Ocular
4.
J Robot Surg ; 18(1): 25, 2024 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-38217741

RESUMO

OBJECTIVES: Patients with inguinal hernia (IH) may have voiding dysfunction and weak urethra-stabilizing periurethral fascial tissues, contributing to urinary incontinence. This study aimed to review the association between IH and urinary continence after robotic-assisted radical prostatectomy (RARP). METHODS: This single-institution retrospective study included 251 consecutive cases of RARP between April 2019 and June 2022. Patients with concurrent IH or a history of adult IH repair were examined. The urine loss rate (ULR), defined as 24-h urine loss volume divided by the total urine volume immediately after urinary catheter removal (i.e., 6 or 7 postoperative days), was compared between the groups with (n = 33) and without IH (n = 214). Possible contributing factors for ULR were assessed, including age, body mass index (BMI), after benign prostatic hyperplasia surgery, prostate weight, and nerve-sparing. ULR was compared intergroup after propensity score matching countering selection biases. RESULTS: Patients with IH were older (71.3 versus. 66.8 years, p < 0.01), had lower BMI (22.8 versus. 24.3, p < 0.01), and had higher ULR (14.5% versus. 5.1%, p < 0.01). In a multiple linear regression analysis (adjusted R2 = 0.084), IH (p < 0.01) was an independent contributing factor for ULR besides advancing age (p < 0.03). After propensity score matching adjusted for patient's age and nerve-sparing, patients with IH had higher ULR (14.1% versus. 5.7%, p < 0.03) as well. CONCLUSIONS: This study first reported that IH may be one of the risk factors of urinary incontinence after RARP.


Assuntos
Hérnia Inguinal , Neoplasias da Próstata , Procedimentos Cirúrgicos Robóticos , Robótica , Incontinência Urinária , Masculino , Adulto , Humanos , Próstata , Estudos Retrospectivos , Procedimentos Cirúrgicos Robóticos/métodos , Hérnia Inguinal/cirurgia , Incontinência Urinária/etiologia , Incontinência Urinária/cirurgia , Prostatectomia/efeitos adversos , Neoplasias da Próstata/cirurgia
5.
Prostate ; 84(5): 502-510, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38173289

RESUMO

BACKGROUND: After brachytherapy, fewer prostate biopsy cores at diagnosis can underestimate the pathological characteristics of prostate cancer (PCa) with lower concordance, resulting in improper treatment, particularly in patients with low-risk nonpalpable cT1c PCa. The aim of this study was to assess the relationship between the number of biopsy cores at diagnosis and long-term clinical outcomes after brachytherapy for cT1c PCa. METHODS: We reviewed 516 patients with localized cT1c PCa with Gleason scores of 3 + 3 = 6 or 3 + 4 = 7 who underwent brachytherapy as monotherapy without hormonal therapy between January 2005 and September 2014 at our institution. Clinical staging was based on the American Joint Committee on Cancer manual for staging. Thus, the cT1c category is based solely on digital rectal examination. The primary outcome was biochemical recurrence (BCR). Based on the optimized cutoff value for biopsy core number obtained from receiver operating characteristic analysis, patients were divided into the biopsy cores ≤8 (N = 123) and ≥9 (N = 393) groups. The BCR-free survival rate was compared between the groups. Prognostic factors for BCR were evaluated, including age, initial prostate-specific antigen (PSA) level, Gleason score, positive core rate, PSA density, prostate magnetic resonance imaging findings, and biopsy core number. RESULTS: The median patient age was 66.0 years (interquartile range [IQR]: 61.0-71.0 years), and the median follow-up time was 11.1 years (IQR: 9.5-13.3 years). The median number of core biopsies was 12 (IQR: 9-12). The area under the curve was 0.637 (95% confidence interval [CI]: 0.53-0.75), and the optimal biopsy core cutoff value for BCR prediction was 8.5 (sensitivity = 43.5%, specificity = 77.1%). Although fewer patients had Gleason scores of 3 + 4 = 7 (19/123 [15%] vs. 125/393 [32%], p < 0.02) in the biopsy cores ≤8 group, the 10-year BCR-free survival rate was significantly lower in the biopsy cores ≤8 group than in the biopsy cores ≥9 group (93.8% vs. 96.3%, p < 0.05). Multivariate analysis revealed that a lower biopsy core number (hazard ratio: 0.828, 95% CI: 0.71-0.97, p < 0.03) and a Gleason score of 3 + 4 = 7 (hazard ratio: 3.26, 95% CI: 1.37-7.73, p < 0.01) significantly predicted BCR. CONCLUSIONS: A low number of prostate core biopsies results in worse BCR-free survival after brachytherapy as monotherapy in patients with cT1c PCa.


Assuntos
Braquiterapia , Neoplasias da Próstata , Masculino , Humanos , Pessoa de Meia-Idade , Idoso , Braquiterapia/métodos , Antígeno Prostático Específico , Próstata/patologia , Biópsia , Estadiamento de Neoplasias
6.
ACS Org Inorg Au ; 3(2): 104-108, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37035279

RESUMO

Organic compounds bearing both silyl and boryl groups are important building blocks in organic synthesis because of the adequate reactivity of the silyl and boryl groups and high stereospecificity in their derivatization reactions. The difference in reactivity between the silyl and boryl groups enables stepwise derivatization of these groups to afford complex molecules. Here, we report the copper(I)-catalyzed silaboration of terminal allenes to produce multisubstituted allylic boronates embedded with an alkenyl silane structure. The reaction can proceed with a variety of allenes and silylboranes. Furthermore, the silyl and boryl groups were successfully converted into other functional groups, while retaining the stereochemistry of the alkene moiety.

7.
Sports Biomech ; : 1-18, 2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36205520

RESUMO

In volleyball, the overhead pass is important. Coaches usually teach players to push the ball, utilising the legs, especially for a long distance pass. The purpose of this study was to conduct a biomechanical analysis of an overhead pass to different distances. Twelve male elite volleyball players participated. They were told to pass a ball with an overhead pass through a 2.43 m high ring located 3 m, 6 m, and 9 m in front of them. Twenty-four reflective markers were placed on the ball and the subject's body to obtain joint centres, joint angles, and ball position. EMG activities were recorded from four right arm muscles. Triceps brachii and flexor carpi radialis pull and push phase activities differed significantly between 3 m and 6 m, but not between 6 m and 9 m. On the other hand, leg movements were significantly different among 3 m, 6 m, and 9 m, suggesting that leg movements supplement the power given to the ball. Thus, as the distance to a target lengthens in an overhead pass, not only arm movement but also leg movement is required.

8.
Sci Rep ; 12(1): 12438, 2022 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-35858947

RESUMO

For older adults especially, to perform everyday activities safely, adaptive locomotion that adjusts basic locomotion pattern according to the environmental features is critical. It is unknown, however, whether their locomotor patterns can be modified when there are subtle environmental changes. We examined adaptive limb movements, focusing on obstacle avoidance and age-related changes during such situations. Younger (102, with a mean age of 27.5 years) and older (101, with a mean age of 78.3 years) participants walked across one obstacle (150 mm height) four different times. The obstacles were then covertly raised or lowered by 10% of the baseline obstacle height (i.e., 165 mm for ascending and 135 mm for descending conditions), and participants were asked to repeat the activity. We measured leading and trailing foot clearances, the vertical distances between toe tips and the upper edge of the obstacle. In the ascending condition, both groups adjusted and raised their limb clearance according to the obstacle height change. Alternatively, foot clearance of the leading limb for the lowered obstacle did not change among the older adults, whereas it changed in the young adults (lowered their clearance). No changes were observed in the trailing foot clearance for the descending conditions in either age group. Our results suggest that when facing environmental changes that compromise safe mobility, individuals can adapt leading limb movement based on subtle environmental changes, irrespective of age. In case of other changes (i.e., in low-risk situations), however, the ability of adaptive locomotion may be affected by aging.


Assuntos
, Locomoção , Adulto , Idoso , Envelhecimento , Fenômenos Biomecânicos , Marcha , Humanos , Extremidade Inferior , Caminhada , Adulto Jovem
9.
J Am Chem Soc ; 144(23): 10483-10494, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35702887

RESUMO

A new series of C1-symmetric P-chirogenic bisphosphine ligands of the type (R)-5,8-Si-Quinox-tBu3 (Silyl = SiMe3, SiEt3, SiMe2Ph) have been developed. The bulky silyl modulators attached to the ligand backbone fix the phosphine substituents to form rigid chiral environments that can be used for substrate recognition. The ligand showed high performances for a copper(I)-catalyzed asymmetric borylative cyclopropanation of bulky silyl-substituted allylic electrophiles to afford higher disfavored 1,2-cis-silyl-boryl-cyclopropanes than the other possible isomers, trans-cyclopropane and allylboronate (up to 97% yield; 98% ee; cis/trans = >99:1; cyclopropane/allylboronate = >99:1). Detailed computational studies suggested that the highly rigid phosphine conformation, which is virtually undisturbed by the steric interactions with the bulky silyl-substituted allyl electrophiles, is key to the high stereo- and product-selectivities. Furthermore, the detailed computational analysis provided insight into the mechanism of the stereoretention or -inversion of the chiral alkylcopper(I) intermediate in the intramolecular cyclization.


Assuntos
Ciclopropanos , Ciclização , Ciclopropanos/química , Ligantes , Conformação Molecular , Estereoisomerismo
10.
Brachytherapy ; 21(4): 451-459, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35461773

RESUMO

INTRODUCTION: Brachytherapy for prostate cancer treatment may induce secondary bladder cancer during long-term follow-ups. This study reviews the risk and tumor characteristics of secondary bladder cancer after brachytherapy. METHODS: This single-institution retrospective study included 1162 patients treated with low-dose-rate permanent seed implantation brachytherapy with iodine-125, with or without external beam radiation therapy, for localized prostate cancer. We calculated and compared the rates of secondary bladder cancer among patients treated with brachytherapy and radical prostatectomy (n = 218) before and after a propensity score-matching analysis. Possible risk factors for secondary bladder cancer, such as patient age and external beam radiation therapy administration, were analyzed. RESULTS: Of 1162 patients with a median follow-up period of 11.4 (range: 0.7-15.5) years, 26 presented with urothelial carcinomas and 1 with adenocarcinoma at a median of 8.9 (range: 2.9-14.0) years after brachytherapy, although the incidence rates of secondary bladder cancer after brachytherapy were not significantly different from those after radical prostatectomy. No significant risk factors for secondary bladder cancer were identified. The initial symptoms of secondary bladder cancer were gross hematuria (74%) and microscopic hematuria with positive urine cytology (15%). Among 26 cases of secondary urothelial carcinoma, 54% were high-grade and 46% were invasive. After brachytherapy, invasive urothelial carcinoma occurred later than noninvasive urothelial carcinoma (p = 0.01). CONCLUSIONS: Considering the aggressive malignancy of secondary bladder cancer, cystoscopy and urine cytology should be performed for further investigation of the causes of gross or microscopic hematuria and rule out secondary bladder cancer in cases followed longer than 3 years after brachytherapy.


Assuntos
Braquiterapia , Carcinoma de Células de Transição , Neoplasias da Próstata , Neoplasias da Bexiga Urinária , Braquiterapia/métodos , Carcinoma de Células de Transição/complicações , Seguimentos , Hematúria/etiologia , Humanos , Radioisótopos do Iodo , Masculino , Neoplasias da Próstata/patologia , Estudos Retrospectivos , Neoplasias da Bexiga Urinária/epidemiologia , Neoplasias da Bexiga Urinária/radioterapia
11.
J Am Chem Soc ; 143(34): 13865-13877, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34424698

RESUMO

Multisubstituted allylic boronates are attractive and valuable precursors for the rapid and stereoselective construction of densely substituted carbon skeletons. Herein, we report the first synthetic approach for differentially 2,3,3-trialkyl-substituted allylic boronates that contain a stereodefined tetrasubstituted alkene structure. Copper(I)-catalyzed regio- and stereoselective three-component coupling reactions between gem-dialkylallenes, alkyl halides, and a diboron reagent afforded sterically congested allylic boronates. The allylboration of aldehydes diastereoselectively furnished the corresponding homoallylic alcohols that bear a quaternary carbon. A computational study revealed that the selectivity-determining mechanism was correlated to the coordination of a boryl copper(I) species to the allene substrate as well as the borylcupration step.

12.
Sci Rep ; 11(1): 12552, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34131185

RESUMO

An association between cognitive impairment and tripping over obstacles during locomotion in older adults has been suggested. However, owing to its memory-guided movement, whether this is more pronounced in the trailing limb is poorly known. We examined age-related changes in stepping over, focusing on trailing limb movements, and their association with cognitive performance. Age-related changes in obstacle avoidance were examined by comparing the foot kinematics of 105 older and 103 younger adults when stepping over an obstacle. The difference in the clearance between the leading and trailing limbs (Δ clearance) was calculated to determine the degree of decrement in the clearance of the trailing limb. A cognitive test battery was used to evaluate cognitive function among older adults to assess their association with Δ clearance. Older adults showed a significantly lower clearance of the trailing limb than young adults, resulting in greater Δ clearance. Significant correlations were observed between greater Δ clearance and scores on the Montreal Cognitive Assessment and immediate recall of the Wechsler Memory Scale-Revised Logical Memory test. Therefore, memory functions may contribute to the control of trailing limb movements, which can secure a safety margin to avoid stumbling over an obstacle during obstacle avoidance locomotion.


Assuntos
Envelhecimento Cognitivo/fisiologia , Disfunção Cognitiva/fisiopatologia , Marcha/fisiologia , Locomoção/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Articulação do Tornozelo/fisiologia , Aprendizagem da Esquiva/fisiologia , Fenômenos Biomecânicos , Cognição/fisiologia , Feminino , Pé/fisiologia , Humanos , Cinética , Masculino , Caminhada/fisiologia , Adulto Jovem
13.
J Am Chem Soc ; 143(17): 6413-6422, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33891398

RESUMO

A new C2-symmetrical P-chirogenic bisphosphine ligand with silyl substituents on the ligand backbone, (R,R)-5,8-TMS-QuinoxP*, has been developed. This ligand showed higher reactivity and enantioselectivity for the direct enantioconvergent borylation of cyclic allyl electrophiles than its parent ligand, (R,R)-QuinoxP* (e.g., for a piperidine-type substrate: 95% ee vs 76% ee). The borylative kinetic resolution of linear allyl electrophiles was also achieved using (R,R)-5,8-TMS-QuinoxP* (up to 90% ee, s = 46.4). An investigation into the role of the silyl groups on the ligand backbone using X-ray crystallography and computational studies displayed interlocking structures between the phosphine and silyl moieties of (R,R)-5,8-TMS-QuinoxP*. The results of DFT calculations revealed that the entropy effect thermodynamically destabilizes the dormant dimer species in the catalytic cycle to improve the reactivity. Furthermore, in the direct enantioconvergent case, detailed calculations indicated a pronounced enantioselective recognition of carbon-carbon double bonds, which is virtually unaffected by the chirality at the allylic position, as a key for the borylation from both enantiomers of racemic allyl electrophiles.

14.
Sports Biomech ; 20(7): 844-857, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31066350

RESUMO

In volleyball, the overhead pass is an important skill for passing a ball and making a set to attackers. In the present study, we analysed the overhead pass motion and involved muscle activity with special attention to the stretch-shortening cycle (SSC). Electromyogram was recorded from the wrist and elbow joint flexors and extensors. The movement period when the ball touched the hand was divided into the pull and push phases with the moment when the ball was at the lowest position. In the pull phase, although the wrists were extended, the activity of wrist flexor muscle was higher than the extensor muscle in both skilled and unskilled groups. And the activity in the wrist flexor muscle in the pull phase was higher in the skilled participants than that of the unskilled participants. Thus, the skilled participants pushed the ball by utilising the SSC of the wrist, while the unskilled participants did this in a less degree. In addition, the kinetic chain was observed from elbow to wrist in the skilled participants. We conclude that it is important for an overhead pass that the wrist flexor muscles accumulate elastic energy during the pull phase which is then released in the push phase.


Assuntos
Desempenho Atlético/fisiologia , Movimento/fisiologia , Músculo Esquelético/fisiologia , Extremidade Superior/fisiologia , Voleibol/fisiologia , Fenômenos Biomecânicos , Eletromiografia , Humanos , Masculino , Análise e Desempenho de Tarefas , Adulto Jovem
15.
Langmuir ; 35(47): 15051-15062, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31671263

RESUMO

We present here the construction of a self-assembled two-dimensional network at the liquid/solid interface using a hexagonal pyridine macrocycle which binds an organic cation in its intrinsic porous space by electrostatic interactions. For this purpose, a hexagonal pyridinylene-butadiynylene macrocycle (PyBM) having six octyloxymethyl groups, PyBM-C8, was synthesized. As guests, tropylium (Tr) tetrafluoroborate and trioxatriangulenium (TOTA) hexafluorophosphate were used. In this study, we focused on (i) the network patterns of PyBM-C8 which change in response to its concentration and (ii) the position of the guest immobilized in the porous space of the macrocycle. Scanning tunneling microscopy (STM) observations at the interface of 1,2,4-trichlorobenzene (TCB) and highly oriented pyrolytic graphite (HOPG) revealed that PyBM-C8 formed four different polymorphs, oblique, loose hexagonal, linear, and rectangular, depending on the solute concentration and annealing treatment. Solvent TCB molecules are likely coadsorbed to not only the intrinsically porous space of PyBM-C8 (internal TCB) but also the space outside of the macrocycle between its alkyl chains (external TCB) in most of the cases. Upon adding the guest cation, whereas small Tr was not visualized in the pore due to size mismatching, larger TOTA was clearly observed in each pore. In addition, based on high-resolution STM images of the rhombus packing pattern of PyBM-C8, we revealed experimentally that TOTA was placed at an off-center position of the deformed hexagonal macrocyclic core in the rhombus pattern. On the basis of the molecular mechanics calculations, we hypothesize that the off-center location of TOTA is due to deformation of the hexagonal macrocycle through interaction with two external TCB molecules located at opposite edges of the macrocyclic core. Symmetry breaking of the macrocyclic host framework induced by coadsorbed surrounding solvent molecules thus plays a significant role in host-guest complexation at the liquid/solid interface.

16.
Angew Chem Int Ed Engl ; 58(32): 11112-11117, 2019 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-31168946

RESUMO

The first copper(I)-catalyzed enantioselective borylation of racemic benzyl chlorides has been realized by a quadrant-by-quadrant structure modulation of QuinoxP*-type bisphosphine ligands. This reaction converts racemic mixtures of secondary benzyl chlorides into the corresponding chiral benzylboronates with high enantioselectivity (up to 92 % ee). The results of mechanistic studies suggest the formation of a benzylic radical intermediate. The results of DFT calculations indicate that the optimal bisphosphine-copper(I) catalyst engages in noncovalent interactions that efficiently recognize the radical intermediate, and leads to high levels of enantioselectivity.

17.
Chem Commun (Camb) ; 54(39): 4991-4994, 2018 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-29707705

RESUMO

We report the first copper(i)-catalysed intramolecular alkylboration of terminal allenes with an alkyl halide moiety. The reaction provides alkenylboronates bearing a four-membered ring structure with high regio- and diastereocontrol. A possible reaction mechanism is proposed, involving the facile isomerization of an allylcopper(i) intermediate. A DFT study explains the experimental regio- and diastereoselectivity.

18.
J Org Chem ; 82(19): 10563-10573, 2017 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-28926233

RESUMO

The copper(I)-catalyzed regio- and stereoselective intramolecular alkylation of propargyl ethers and amines bearing an alkyl electrophilic moiety has been developed. The reaction showed high functional group tolerance and gave highly functionalized alkenylboronates bearing heterocyclic rings, which are versatile synthetic intermediates in organic chemistry. The borylation products can be transformed into multisubstituted alkenes through stereospecific transformations. Mechanistic studies showed that the chemo- and stereoselectivity of copper(I)-catalyzed borylation depends on the type of leaving group. Density functional theory calculations suggested that the regioselectivity of the borylcupration of the alkyne is controlled by the electronic effect of the oxygen atom of the propargyl ether in combination with the steric congestion between the boryl group and the substituent at the propargylic position.

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