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1.
Food Chem ; 438: 137962, 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-37976872

ABSTRACT

The coconut shell-based activated charcoal was decorated by three different electronegativities of surfactants (CTAB, SDS, and Triton X-100) through the impregnation method, and the decorated activated charcoal adsorbents were used for the removal of PAHs from peanut oil, respectively. The influence of surfactant decoration on the adsorption and detoxification effect of coconut shell-based activated charcoal was discussed. The thermodynamic and kinetic behaviors of PAHs adsorption on the surfactant-modified activated charcoal were investigated, and the adsorption mechanism was analyzed in-depth. Notably, the prepared modified coconut shell activated charcoal could not only remove more than 90% of PAHs from the peanut oil but also keep the cytotoxicity of the treated peanut oil low. Meanwhile, the detoxification procedure has little effect on the nutritional quality and flavor of the peanut oil. The results of this fundamental study demonstrate that the low-cost surfactant-modified coconut shell-based activated charcoal was effective and feasible.


Subject(s)
Polycyclic Aromatic Hydrocarbons , Water Pollutants, Chemical , Surface-Active Agents , Charcoal , Octoxynol , Cetrimonium , Cocos , Peanut Oil , Lipoproteins , Cations , Adsorption
2.
Mycotoxin Res ; 40(1): 45-70, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38133731

ABSTRACT

Mycotoxins in agricultural commodities have always been a concern due to their negative impacts on human and livestock health. Issues associated with quality control, hot and humid climate, improper storage, and inappropriate production can support the development of fungus, causing oil crops to suffer from mycotoxin contamination, which in turn migrates to the resulting oil, de-oiled cake and meals during the oil processing. Related research which supports the development of multi-mycotoxin prevention programs has resulted in satisfactory mitigation effects, mainly in the pre-harvest stage. Nevertheless, preventive actions are unlikely to avoid the occurrence of mycotoxins completely, so removal strategies may still be necessary to protect consumers. Elimination of mycotoxin has been achieved broadly through the physical, biological, or chemical course. In view of the steadily increasing volume of scientific literature regarding mycotoxins, there is a need for ongoing integrated knowledge systems. This work revisited the knowledge of mycotoxins affecting oilseeds, food oils, cake, and meals, focusing more on their varieties, toxicity, and preventive strategies, including the methods adopted in the decontamination, which supplement the available information.


Subject(s)
Mycotoxins , Humans , Mycotoxins/analysis , Plant Oils , Food Contamination/prevention & control , Food Contamination/analysis , Fungi , Crops, Agricultural , Meals
3.
J Food Sci ; 88(10): 4028-4045, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37589301

ABSTRACT

To facilitate the typical flavor of sunflower oil, seed roasting is widely applied. In this study, the effects of seed-roasting degree (160, 180, 200°C for 0-25 min) on the quality attributes of sunflower oil were assessed, particularly tocopherols, sterols, total phenolics, fatty acids, and triglycerides composition as essential compounds for the nutritional value of the sunflower oil. Roasting seeds at a high temperature can significantly raise oxidative stability by 1.5-1.8 times, the content of carotenoids by 2.0-5.5 times, chlorophyll by 7.5-17.0 times, as well as increase the browning index by 4.0-10.0 times and deepen the color of the sunflower oil. However, the fatty acid and triglyceride profiles of sunflower oils have little change under distinct seed-roasting degrees. Synthetically considering the various indicators measured in the current study. It is recommended that the seed roasts at 160-180°C for about 20 min to ameliorate the oxidative stability and quality. Practical Application: A well-defined roasting process is very important for the food industry to be able to produce sunflower oil with desirable nutrition, unique flavor produced by the Maillard reaction and chemical properties of sunflower oil, which changes during the roasting. Considering the flavor, peroxide values, oxidation stability, and other quality attributes of oil obtained from the roasted seed, we found that sunflower seed oil better quality is obtained when roasted at 160- -180°C for about 20 min (e.g., 160°C for 20-25 min or 180°C for 15-20 min).

4.
Food Addit Contam Part B Surveill ; 15(4): 275-282, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35854473

ABSTRACT

Aflatoxins have been detected as contaminants of oil crops before harvesting and drying, during storage and manufacturing and could be transferable to plant oils. There are more than 20 different types of aflatoxins, among which the most commonly occurring are the B1, B2, G1 and G2. Concentrations of these four aflatoxins were determined in plant oils from retail shops in China and in crude peanut oil extracted from culled mouldy peanuts by HPLC with fluorescence detection. Overall, aflatoxins were present in 25 of the 63 samples. The four aflatoxins co-existed in vegetable oil, but the content of AFB1 was usually higher than the other aflatoxins. Particularly in the case of highly contaminated oil samples, AFB1 accounted for 68% of the total aflatoxins. According to the health risk assessment, the low margin of exposure values from AFB1 in oils suggests a high level of concern for children.


Subject(s)
Aflatoxins , Humans , Child , Aflatoxins/analysis , Aflatoxin B1/analysis , Food Contamination/analysis , Peanut Oil , Arachis , Plant Oils/analysis , Chromatography, High Pressure Liquid
5.
Food Chem ; 339: 128072, 2021 Mar 01.
Article in English | MEDLINE | ID: mdl-33152867

ABSTRACT

The efficient magnetic adsorbent (Fe3O4@ATP) was prepared by precipitation through the dispersion of Fe3O4 nanoparticles on the natural attapulgite (ATP) and then tested as an adsorbent for aflatoxin B1 (AFB1) removal from contaminated oils. The adsorbent characterization results revealed that the Fe3O4 were incorporated into the ATP, affording the Fe3O4@ATP composite. This magnetic composite displayed a good ability to eliminate AFB1 from contaminated oils with a removal efficiency of 86.82% using a 0.3% dosage. The Fe3O4@ATP possessed paramagnetic character with a saturation magnetization of 50.86 emu/g, enabling its easy separation from the medium using an external magnet. The adsorption process followed the pseudo-second-order model and fitted the Freundlich isotherm well. Moreover, the thermodynamic studies showed that AFB1 adsorption onto Fe3O4@ATP was exothermic and spontaneous. The novelty of this study lies in the fabrication of magnetic composite adsorbents for AFB1 elimination from oils.


Subject(s)
Aflatoxin B1/isolation & purification , Arachis/chemistry , Food Contamination , Magnesium Compounds/chemistry , Magnets/chemistry , Plant Oils/chemistry , Silicon Compounds/chemistry , Adsorption , Aflatoxin B1/chemistry , Kinetics , Thermodynamics
6.
J Hazard Mater ; 381: 120915, 2020 01 05.
Article in English | MEDLINE | ID: mdl-31352149

ABSTRACT

Safety concerns pertaining towards fungal occurrence in oil commodities have been a significant threat to human health. In this research, magnetic composite adsorbents were fabricated for the removal of aflatoxin B1 (AFB1) from contaminated oils. To this goal, graphene oxides (GO) were synthesized using Hummer's method, and graphenes (rGO) were obtained by the reduction of GO by sodium borohydride. Thereafter, magnetic graphene oxides (MGO) and magnetic graphenes (MrGO) were prepared by coprecipitation of iron oxides on GO and rGO nanosheets, respectively. The as-prepared MGO and MrGO were characterized by SEM, TEM, FT-IR, XRD, VSM, and nitrogen adsorption-desorption techniques. Results showed that MGO had two-dimensional layered nanostructure with many wrinkles on its surface, and the Fe3O4 nanoparticles were essentially encapsulated onto the composite. The adsorption behaviors for the composite adsorbents especially for the removal of AFB1 from contaminated oils were systematically explored by varying adsorbent dosage, contact time, adsorption temperature and initial AFB1 concentration. The MGO adsorbent could have great potential in the application of AFB1 removal from contaminated oils, with the merits of facile magnetic separation and high removal efficiency. However, the removal process also causes a loss of the triglyceride, pigment, and beneficial micronutrients in the oil feedstocks.


Subject(s)
Aflatoxin B1/chemistry , Graphite/chemistry , Magnetite Nanoparticles/chemistry , Nanocomposites/chemistry , Rice Bran Oil/chemistry , Adsorption , Food Safety , Magnetic Phenomena
7.
Coron Artery Dis ; 31(4): 372-377, 2020 06.
Article in English | MEDLINE | ID: mdl-31860558

ABSTRACT

OBJECTIVE: We aimed to detect the synergistic effect between alcohol drinking, smoking and obesity on incident cardiovascular disease (CVD) in a Chinese population- based cohort. METHODS: We performed this study based on a prospective cohort based on a Chinese population in Jiangsu, China. Logistic regression was employed to detect the interaction of smoking, drinking with obesity on susceptibility to CVD, and calculate the odds ratio (OR) of CVD and corresponding 95% confidence interval (CI). RESULTS: A total of 3598 subjects (1451 males and 2147 females) were enrolled, including 82 CVD patients (36 males and 46 females) who new developed CVD at the follow-up. We found a significant abdominal obesity-current smoking interaction on CVD risk. Compared to never-smokers with normal waist circumference, OR (95% CI) of CVD were 2.44 (1.56-3.81), 1.58 (0.93-2.69), and 5.37 (3.08-9.34) for smokers with normal waist circumference, abdominal obese nonsmokers and abdominal obese smokers, respectively. Synergy index for this interaction was 2.35 (1.05-4.50). We also found a significant abdominal obesity-alcohol drinking interaction on CVD. Compared to never-drinkers with normal waist circumference, OR (95% CI) of CVD were 1.57 (1.01-2.45), 1.84 (1.08-3.12), and 4.44 (2.55-7.72) for drinkers with normal waist circumference, abdominal obese non- drinkers and abdominal obese drinkers, respectively. Synergy index for this interaction was 2.44 (1.04-5.72). CONCLUSION: We found significant interactions between alcohol drinking and abdominal obesity, smoking and abdominal obesity on CVD risk, suggested that the effect of alcohol drinking or smoking on CVD susceptibility seems to be modified by abdominal obesity.


Subject(s)
Alcohol Drinking/adverse effects , Cardiovascular Diseases/etiology , Obesity/complications , Smoking/adverse effects , Adult , Aged , Alcohol Drinking/epidemiology , Body Mass Index , Cardiovascular Diseases/epidemiology , China/epidemiology , Female , Follow-Up Studies , Humans , Incidence , Male , Middle Aged , Obesity/epidemiology , Prospective Studies , Risk Factors , Smoking/epidemiology , Survival Rate/trends
8.
J Oleo Sci ; 68(8): 709-718, 2019 Aug 01.
Article in English | MEDLINE | ID: mdl-31292341

ABSTRACT

Foxtail millet (FM) is one of the oldest cultivated grain crops with a variety of nutritions, and foxtail millet bran (FMB), a by-product of FM milling process, is also rich in variety of nutrient substance. There are four classifications of FMB, namely coarse bran (FMCB), skin bran (FMSB), polished bran (FMPB) and mixed bran (FMMB). Because these nutrients are distributed within the different fractions of FMB, we compared some chemical composition and its oleochemical properties of four FMB samples. Results showed that the oil extracted from FMB is high value-added plant oil. It contains abundant unsaturated fatty acid (UFA), with the main UFAs were linoleic acid (65%~69%) and oleic acid (12~17%), which accounted for more than 80% of the lipids. The main triacylglycerols were trilinolein (LLL) and oleodilinolein (OLL). There were no evident difference on fatty acid, triacylglycerol and sterols profiles for FMSB, FMPB and FMMB, but the contents of amino acids, tocols, squalene and oryzanol were different.


Subject(s)
Dietary Fiber/analysis , Plant Oils/analysis , Setaria Plant/chemistry , Plant Oils/chemistry
9.
Wei Sheng Yan Jiu ; 48(1): 99-108, 2019 Jan.
Article in Chinese | MEDLINE | ID: mdl-31032776

ABSTRACT

OBJECTIVE: To establish a recombinase polymerase amplification(RPA) method for extensively resistant pathogen screening and rapid detection in the field for rapid amplification of the metallo-beta-lactamase gene bla_(NDM). METHODS: Specific conservative sequence had been selected as target genes by sequence comparative analysis. The primers and probes for RPA assays were designed according to the principle of RPA amplification requirements. A descending gradient diluted template genes were used for RPA detection to determine the sensitivity. Reference templates of other resistant types of bacteria were used to analysis the specificity of amplification reaction systems. The amplification reaction systems were also conducted repeatedly for verifying the repeatability. RESULTS: Three of the RPA reaction systems could effectively amplify the target genes, the sensitivities reach 2×10~2 copies. No one cross reaction existed with the other drug-resistant bacteria DNA. All the reactions can be completed between two to seven minutes. CONCLUSION: The RPA assays of the metallo-beta-lactamase gene bla_(NDM) are established, which may amply target genes fast and have a lower detection limit, and be potentially useful for in field pathogens detection.


Subject(s)
DNA Primers , Drug Resistance , Recombinases , beta-Lactamases , Bacteria/genetics , Drug Resistance/genetics , Molecular Diagnostic Techniques , Real-Time Polymerase Chain Reaction , Recombinases/genetics , Sensitivity and Specificity
10.
J Oleo Sci ; 68(1): 13-20, 2019 Jan 01.
Article in English | MEDLINE | ID: mdl-30542005

ABSTRACT

To develop and use the hazelnut, the main composition, and the physicochemical characteristics, fatty acid compositions, triacylglycerol (TAG) distribution and tocol contents of Hazelnut (Corylus mandshurica Maxim.) which growing in Changbai mountain of Jilin province (HO1) and Anshan city of Liaoning province (HO2) in China were investigated, and the comparative study between the two hazelnut oils and American hazelnut / Turkish hazelnut were also explored. The content of crude lipid and protein in HO1 and HO2 were approximately 54% and 17%, 55% and 16%, respectively. The two hazelnut oils were abundant in unsaturated fatty acids, with the primary unsaturated fatty acids were oleic acid (78%-80%) and linoleic acid (14-16%), which accounted for above 90% of the oils. Therefore, both of the hazelnut oils were important sources of essential fatty acid. In addition, the main saturated fatty acid of the two hazelnut oils were palmitic acid (3%) and stearic acid (1-2%). The main triacylglycerols (TGA) profile were dioleolinolein (OOL), oleodilinolein (OLL) and triolein (OOO). The contents of tocol were 574.44 µg/g, 647.49 µg/g oil in HO1 and HO2, respectively, both of them were higher than that of grape seed oils (454 µg/g), olive oils (209 µg/g) and walnut oils (255 µg/g). The total phytosterol contents were over 2000µg/g and ß-sitosterol was the most predominant sterol in two oils.


Subject(s)
Corylus/chemistry , Lipids/analysis , Fatty Acids/analysis , Fatty Acids/isolation & purification , Lipids/isolation & purification , Phytosterols/analysis , Phytosterols/isolation & purification , Plant Oils/analysis , Plant Oils/isolation & purification , Tocopherols/analysis , Tocopherols/isolation & purification , Tocotrienols/analysis , Tocotrienols/isolation & purification , Triglycerides/analysis , Triglycerides/isolation & purification
11.
Inflamm Res ; 65(7): 573-8, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27022745

ABSTRACT

AIMS: The aim of this study was to investigate the impact of the signal transducer and activator of transcription 3 (STAT3) gene and additional STAT3 gene-smoking interaction on Crohn's disease (CD) risk based on a Chinese population. METHODS: A total of 1012 participants (491 men, 521 women), were selected, including 502 CD patients and 510 normal controls. The mean age of all participants was 42.3 ± 11.2 years. Logistic regression model was used to examine the association between single nucleotide polymorphism (SNP) of STAT3 and CD risk; the odds ratio (OR) and 95 % confident interval (95 % CI) were calculated. Generalized multifactor dimensionality reduction was employed to analyze the interaction among several SNPs. RESULTS: Logistic analysis showed the significant association between genotypes of variants in two SNP and decreased CD risk, after covariates adjustment. The carriers of homozygous mutant of two SNP polymorphism revealed decreased CD risk than those with wild-type homozygotes; OR (95 % CI) was 0.75 (0.59-0.93) and 0.68 (0.57-0.91), respectively. There was a significant two-locus model (p = 0.0107) involving rs744166 and smoking, indicating a potential gene-environment interaction between rs744166 and smoking. Overall, the cross-validation consistency was 10/10, and the testing accuracy was 62.17 %, and never smokers with TC or CC genotype have the lowest CD risk, compared to smokers with TT genotype; OR (95 % CI) was 0.52 (0.31-0.82), after covariate adjustment. CONCLUSIONS: Our results support an important association of rs744166 and rs4796793 with decreased CD risk, and additional interaction between rs744166 and smoking.


Subject(s)
Asian People/genetics , Crohn Disease/genetics , STAT3 Transcription Factor/genetics , Smoking/genetics , Adult , Case-Control Studies , China/epidemiology , Crohn Disease/epidemiology , Female , Genotype , Humans , Male , Middle Aged , Odds Ratio , Polymorphism, Single Nucleotide , Smoking/epidemiology
12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(9): 2387-90, 2014 Sep.
Article in Chinese | MEDLINE | ID: mdl-25532331

ABSTRACT

In the present paper, 60 whole wheat flour samples were prepared and corresponding NIR spectra were collected. After the determinations of calibration range, several spectral sub-regions containing calibration range and prepared for the correction using multiple scattering correction (MSC) were obtained in the whole spectral region firstly, and MSC correction based on different spectral sub-region followed subsequently. Corresponding spectral data were obtained from the fixed calibration range of the spectra corrected based on different regions. Several partial least squares regression (PLSR) calibration models for analyzing protein content of whole wheat flour were established based on corresponding spectral data, and according to the performance about the calibration coefficient and the root mean square error of cross validation (RMSEV) of every calibration, the effects of MSC pretreatment spectral region on PLSR calibration results were investigated and the pretreatment spectral regions were optimized by comparing theperformance of more calibration models. For the optimized calibration, the calibration coefficient and the RMSECV improved compared with the calibration established based on the spectral data corrected using MSC in the fixed region of calibration. The correlation coefficient can be raised from 0.96 to 0.98 and RMSECV can be decreased from 0.37% to 0.32%. The results show that the capability of MSC on correcting the spectral interference information of non-chemical absorption can be influenced by preprocessing spectral regions, the performance of calibration model can be improved by optimizing the MSC pretreatment spectral region, and the appropriate pretreatment spectral region is prerequisite to obtain the best calibration results while using MSC for near-infrared spectra analysis.

13.
Int Arch Occup Environ Health ; 83(4): 399-406, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20151308

ABSTRACT

AIM: To determine the sensitive and convenient biomarkers for the early detection of hepatic injury in N,N-dimethylformamide (DMF) exposed workers. METHODS: Seventy-nine individuals in a synthetic leather factory were investigated with questionnaire survey. The air samples, urine samples, and blood samples were collected at the specific time point. Airborne DMF and the urine metabolites of DMF were measured by gas chromatography (GC), high-performance liquid chromatography (HPLC), and gas chromatography-mass spectrometry (GC-MS). Traditional liver function tests and hepatic fibrosis parameters were performed by auto-chemistry analyzer and ELISA methods. RESULTS: The urine concentration of N-acetyl-S-(N-methylcarbamoyl)-cysteine (AMCC), one of the metabolites of DMF, was positively correlated with activities of liver function enzymes. About 60% subjects with urine AMCC concentration above 40 mg/g creatinine showed raised liver enzymes activities. In terms of hepatic fibrosis parameters, we found 4 of 5 abnormal total serum bile acid (SBA) and 4 of 4 abnormal serum hyaluronidase (HA) among workers with higher amount of urine AMCC. CONCLUSION: Workers exposed to DMF with higher urine AMCC levels were more likely to develop liver diseases. In addition, SBA and HA have the potential to act as early indicators of toxic hepatic fibrosis activities for occupational health surveillance.


Subject(s)
Acetylcysteine/analogs & derivatives , Chemical and Drug Induced Liver Injury/urine , Environmental Monitoring/methods , Formamides/toxicity , Occupational Exposure/adverse effects , Acetylcysteine/urine , Adult , Bile Acids and Salts/blood , Biomarkers/urine , Chemical and Drug Induced Liver Injury/blood , China , Dimethylformamide , Female , Humans , Hyaluronoglucosaminidase/blood , Liver Function Tests , Male , Middle Aged , Textile Industry
14.
Article in Chinese | MEDLINE | ID: mdl-16105445

ABSTRACT

OBJECTIVE: To analyse the male reproductive toxicity of carbaryl. METHODS: Thirty-one male carbaryl exposure workers and 46 male administrators in the office in a pesticide factory were selected as the exposure group and internal control group respectively, and 22 male administrators in a center for disease control and prevention were served as the external control group. In order to evaluate the exposure levels, the concentrations of carbaryl, methyl isocyanate, ammonia and phenol in the ambient air of the work place in these three groups were monitored simultaneously for three consecutive days. Moreover, three workers in the exposure group and the external control group were selected to evaluate the amount of carbaryl of individual and dermal contamination for three consecutive days. After the semen were collected according to the standard method, the workers'semen qualities were analysed with WHO method, the sperm morphology and the sperm motility were evaluated using micro-cell slide spectrum technology and computer assisted sperm analysis (CASA) respectively. RESULTS: In the exposure group, the concentrations of carbaryl and phenol (52.41 mg/m(3) and 0.08 mg/m(3) respectively) were significantly higher than those in the internal and external control group (P < 0.01 or P < 0.05). Furthermore, in the carbaryl exposure area the geometric mean concentration of carbaryl with the individual sampling was 7.38 mg/m(3), and the geometric mean of dermal contamination detected in the carbaryl exposure area was 862.47 mg/m(2). Carbaryl was not found in the external control area (P < 0.01). The seminal volume [(2.39 +/- 1.44) ml] and the sperm motility [(1.77 +/- 0.61) grade] were significantly lower than those in the external control group (P < 0.05), and sperm motion parameters such as linearity (LIN, 39.89% +/- 6.00%), straightness (STR, 71.51% +/- 11.22%), straight line velocity [VSL, (26.29 +/- 7.84) microm/s] and beat cross frequency [BCF, (3.99 +/- 1.55) Hz] were lower than those in the internal and external control group (P < 0.05), while the abnormal rates of viscidity, sperm motility and total aberration rate were higher than those in the external control group (P < 0.05). CONCLUSION: Occupational exposure to carbaryl production can affect the workers'sperm and semen quality to certain extent.


Subject(s)
Carbaryl/adverse effects , Insecticides/adverse effects , Occupational Exposure , Semen/drug effects , Spermatozoa/drug effects , Adult , Humans , Male , Sperm Motility/drug effects , Spermatozoa/abnormalities
15.
Zhonghua Nan Ke Xue ; 8(4): 273-6, 2002.
Article in Chinese | MEDLINE | ID: mdl-12491693

ABSTRACT

OBJECTIVES: To study the effects of fenvalerate exposure on the semen quality of occupational workers in order to find out the early effective biomarkers. METHODS: Thirty-two male workers who exposed to fenvalerate and 46 male administrators in the office in a pesticide factory were selected as the exposure group and internal control group, respectively, and 22 male administrators in a center for disease control were served as the external control group. In order to evaluate the exposed levels, the concentration of fenvalerate, toluene and xylene in the ambient air of working place in these three groups were monitored simultaneously for three consecutive days. After the semen were collected according to the standard method, the workers' semen qualities were analysed with University of California at Davis (UCDavis) method and the sperm motility were evaluated using computer assisted sperm analysis(CASA). RESULTS: In the exposure group, the concentrations of fenvalerate were significantly higher than those in the internal and external control group (P < 0.01), while no significant difference of the concentration on toluene or xylene was found (P > 0.05). Sperm motion parameters in the exposure group such as linearity(LIN), straightness(STR), and the sperm count were decreased significantly, and the abnormality rate of viscidity, coagulation and sperm count were increased significantly as compared with the internal and the external control groups(P < 0.05). Furthermore, the sperm progression and beat cross frequency (BCF) in the exposure group were also lower significantly than those in the external control group(P < 0.05), while the abnormality rate of sperm progression was increased significantly. CONCLUSIONS: In such a low concentration, occupational exposure to fenvalerate can affect workers' semen quality, especially the sperm count and sperm movement ability.


Subject(s)
Insecticides/toxicity , Occupational Exposure/adverse effects , Pyrethrins/toxicity , Semen/drug effects , Adult , Humans , Male , Nitriles , Sperm Count , Sperm Motility/drug effects
16.
Inorg Chem ; 41(18): 4775-9, 2002 Sep 09.
Article in English | MEDLINE | ID: mdl-12206704

ABSTRACT

The reactions of Me(3)SiN=P(OR")RR'(R" = Ph, CH(2)CF(3); R, R' = Me, Ph) with alcohols were investigated. With nonequivalent amounts of CF(3)CH(2)OH, the reactions produced high yields of the cyclic phosphazene (Me(2)PN)(3) and both the cis and trans isomers of nongeminally substituted [(Ph)(Me)PN](3). The isomers of this new cyclic phosphazene were separated by column chromatography and characterized by NMR and IR spectroscopy, elemental analysis, and X-ray crystallography. Crystals of the cis isomer 6a have a monoclinic crystal system, while the trans isomer 6b has a triclinic crystal system with two different molecules in an asymmetric unit. The bond lengths and bond angles are very similar to those of the simpler cyclic trimers (Me(2)PN)(3) and (Ph(2)PN)(3.) A likely pathway for the formation of these compounds is discussed.

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