手性磺酰胺的合成及在苯乙酮的不对称氢转移反应中的应用

以辛可宁为原料,经Mitsunobu反应合成了9-氨基(9-脱氧)表辛可宁,然后分别与8-喹啉磺酰氯、苯磺酰氯、对甲基苯磺酰氯、对氯苯磺酰氯反应,合成了4个手性磺酰胺化合物.对这些磺酰胺在苯乙酮的不对称氢转移反应中的催化性能进行了考察,在80℃下反应,当n(苯乙酮):n(手性磺酰胺Ru(Ⅱ)配合物):n(氢氧化钾)=50:1:2.5时,获得的最大转化率为96.0%.     

左旋多巴醇在不对称还原中的应用研究

在NaBH4/Cd2+、NaBH4/Co2+、NaB4/Ce3+、NaBH4/Ni3+还原体系中,采用加入手性源左旋多巴醇和不加入左旋多巴醇两种方法,分别对苯乙酮进行不对称还原,结果表明,加入手性源左旋多巴醇后,反应速度快,产率高.同时在这4种还原体系中NaBH4/Ce3+的催化效果最好.     

生物催化羰基不对称还原合成手性醇的研究及应用进展

综述了国内外利用生物催化羰基的不对称还原合成手性醇的研究情况。介绍了生物催化各类潜手性羰基化合物不对称还原的原理、菌种的筛选,以及生物催化不对称还原各类羰基化合物的实例。     

樟脑衍生的手性磺酰胺醇的合成及催化性能

由天然樟脑合成了一个新手性磺酰胺醇,并对其在二乙基锌对苯甲醛的对映选择性加成中的催化性能进行了研究,获得了73%化学产率和9.2%e.e.。     

面包酵母用于苯乙酮的不对称还原研究

研究了面包酵母用于苯乙酮的不对称还原,分别考察了反应温度,反应时间,催化剂用量等因素对转化率和对映体选择性的影响。     

新手性磺酰胺醇催化二乙基锌对苯甲醛的不对称加成反应

由天然樟脑和(L)-苯丙氨酸合成了4个新的手性磺酰胺醇,并对其在二乙基锌对苯甲醛的不对称加成中的催化性能进行了研究。这4个手性磺酰胺醇表现出中等程度的催化活性和较差的不对称诱导作用。     

促进活性细胞催化前手性羰基不对称还原研究进展

利用活性微生物细胞催化羰基不对称还原成为手性醇合成的重要方法。虽然当前已经筛选出许多立体选择性很高的微生物和反应过程,但这类反应能实际应用的还很少,主要是因为产业化方面的研究不够。本文从此出发,结合作者近几年的研究工作对当前活性微生物细胞催化羰基不对称还原相关工程方面的研究进行了详细的介绍和论述。分析了利用活性细胞催化时空产率低的原因,对国内外研究者针对这些原因为提高时空产率所进行的各种研究和提出的方法分别进行了归纳和分析。     

基因工程菌在不对称还原制备手性醇中的应用进展

综述了基因工程菌在手性醇合成中的研究情况。介绍了合成手性醇的酶学研究及酶的基因特性,重点阐述了工程菌的质粒构建及表达体系对不对称合成的催化效率和立体选择性的影响,并对基因工程菌不对称还原制备手性醇的应用前景进行了展望。     

热带假丝酵母不对称还原3,5-双三氟甲基苯乙酮制备手性醇(英文)

(S)-3,5-bistrifluoromethylphenyl ethanol is a key chiral intermediate for the synthesis of NK-1 receptor antagonists. Enantioselective synthesis of (S)-3,5-bistrifluoromethylphenyl ethanol was successfully performed in high enantiomeric excess (e.e.) through asymmetric reduction of 3,5-bis(trifluoromethyl) acetophenone catalyzed by Candida tropicalis 104 cells. The influence of some key reaction parameters such as substrate concentration, co-substrate and its concentration, biomass and reaction time was examined, respectively. The results showed that these factors obviously influence the yield, but the optical purity of the prepared product remains intact. The opti-mum conditions for the preparation of (S)-3,5-bistrifluoromethylphenyl ethanol were found to be as follows: sub-strate concentration 50 mmol?L?1; 50 g·L-1 of maltose as co-substrate; wet cell concentration 300 g·L-1; reaction for 30 h. Under above optimal conditions, the maximum yield for (S)-3,5-bistrifluoromethylphenyl ethanol reached 70.3% with 100% of product e.e.     

氨基醇配体催化不对称合成反应研究进展

在不对称催化反应中,手性氨基醇是一类非常重要的手性配体,它们可用于催化多种不对称合成反应。本文综述了近年来国内外手性氨基醇配体催化各种不对称合成反应的研究新进展,为开发更高效的氨基醇配体提供了参考。     

利用植物催化剂不对称还原反应生产手性芳香醇(英文)

Chiral aromatic alcohols are the key chiral building block for many important enantiopure pharmaceu-ticals. In this work,we studied asymmetric reduction of prochiral aromatic ketone to produce the corresponding chiral alcohol using vegetables as the biocatalyst. Acetophenone was chosen as the model substrate. The results in-dicate that acetophenone can be reduced to the corresponding chiral alcohols with high enantioselectivity by the chosen vegetables,i.e. apple(Malus pumila),carrot(Daucus carota),cucumber(Cucumis sativus),onion(Allium cepa),potato(Soanum tuberosum),radish(Raphanus sativus),and sweet potato(Ipomoea batatas) . In the reaction,R-1-phenylethanol is produced with apple,sweet potato and potato as the catalyst,while S-1-phenylethanol is the product with the other vegetables as the catalyst. In term of the enantioselectivity and reaction yield,carrot(D. ca-rota) is the best catalyst for this reaction. Furthermore,the reaction characteristics were studied in detail using car-rot(D. carota) as the biocatalyst. The effects of various factors on the reaction were investigated and the optimal reaction conditions were determined. Under the optimal reaction conditions(reaction time 50 h,substrate concen-tration 20 mmol·L-1,reaction temperature 35 °C and pH 7),95% of e.e.(to S-1-phenylethanol) and 85% chemical yield can be obtained. This work extends the biocatalyst for the asymmetric reduction reaction of prochiral aromatic ketones,and provides a novel potential route to produce enantiopure aromatic alcohols.     

含氮外消旋配体金属络合物在苯乙酮不对称氢转移反应中的应用

本文将(1S,2S)-1,2-二苯基乙二胺、(±)-1,1'-联-2-萘胺以及过渡金属络合物二-μ-氯-二(1,5-环辛二烯)二铑组成的催化剂体系用于催化苯乙酮的不对称氢转移反应,通过气相色谱法及旋光测定法对反应物的转化率及产物的光学纯度进行了分析和测定。     

解脂耶氏酵母不对称还原苯乙酮合成(R)-苯乙醇

为了提高解脂耶氏酵母对苯乙酮的催化效率,以20mmol/L的苯乙酮和苯乙醇为筛选压力,采用紫外诱变获得突变株,优化了反应体系参数,如温度、pH值、辅助底物、有机溶剂(如甲苯、己烷、辛烷、DMF、DMSO等)以及离子液体(1-丁基-3-甲基咪唑六氟磷酸盐,BMIM·PF6)等对催化体系的影响。结果表明,利用解脂耶氏酵母突变株全细胞催化苯乙酮(20mmol/L)合成(R)-苯乙醇,转化率76%,e.e.达99.2%。优化后的反应体系如下:最适辅助底物为葡萄糖,反应温度30℃,pH=7.0,30%(体积分数)疏水性离子液体BMIM·PF6。当利用解脂耶氏酵母突变株的发酵液为催化体系,向反应体系中添加30%(体积分数) BMIM·PF6,以60mmol/L苯乙酮为底物,反应36h,(R)-苯乙醇的转化率达95%,e.e.值达97%。解脂耶氏酵母突变株全细胞催化苯乙酮不对称还原反应,在高底物浓度、高转化率以及高光学纯度等方面具有突出表现。     

钌配合物催化苯乙酮的氢转移还原反应的研究

在空气气氛条件下,对钌配合物催化苯乙酮听氢转移还原反应作了详细的考察,取得了较好的结果,使反应更加方便快捷。考察了ＲｕＣｌ３、ＲｕＣｌ３／Ｌｎ〗Ｌｎ＝邻苯二胺（简称ＰＤＡ）、邻氨基酚（简称ＡＰＯ）、邻氨基苯甲酸（简称ＡＢＡ）、２,２＇－联吡啶（简称ＢＩＰＹ）〖及ＲｕＣｌ２（ＰＰＨ３）３这种催化剂对苯学原为苯乙醇的经效果。实验表明,在异丙醇作为溶剂及提供氢源的情况下,以少量Ｎａ#作为助催化剂,Ｒｃ／     

Asymmetric reduction of chloroacetophenones to produce chiral alcohols with microorganisms

Four strains of yeast with reduction activity of chloroacetophenones were screened, in which Saccharomyces cerevisiae B5 showed best reduction activity and stereoselectivity. High optical purity (R)-2′-chloro-1-phenylethanol can be obtained with Saccharomyces cerevisiae B5 as biocatalyst. The influence of several co-substrates on the enantiometric excess (ee%) and yield of (R)-2′-chloro-1-phenylethanol was evaluated. 5% (v/v) ethanol is optimal cosubstrate for (R)-2′-chloro-1-phenylethanol formation. The optimal bioconversion conditions of 2′-chloroacetophenone catalyzed by Saccharomyces cerevisiae B5 are as follows: pH 8.0, 25 °C and 24 h. The yield and the enantiometric excess of (R)-2′-chloro-1-phenylethanol can both reach more than 99% with 10.75 g/l Saccharomyces cerevisiae B5 (the cell dry weight) and 1 g/l 2′-chloroacetophenone used in the biotransformation.     

手性醇诱导下联萘酚的固相不对称合成

利用三种含羟基的手性化合物D 葡萄糖缩二丙酮、D 甘露醇缩二丙酮、胆固醇构筑不对称环境,三氯化铁作为氧化剂,固相不对称合成联萘酚,产率最高达91.5%,同时光学收率达14.6%。