Chemoselective Oxidation of Equatorial Alcohols with N-Ligated λ<sup>3</sup>-Iodanes
作者:Myriam Mikhael、Sophia A. Adler、Sarah E. Wengryniuk
DOI:10.1021/acs.orglett.9b02018
日期:2019.8.2
of nitrogen-ligated (bis)cationic λ3-iodanes (N-HVIs) for alcoholoxidation and their unprecedented levels of selectivity for the oxidation of equatorial over axial alcohols. The conditions are mild, and the simple pyridine-ligated reagent (Py-HVI) is readily synthesized from commercial PhI(OAc)2 and can be either isolated or generated in situ. Conformational selectivity is demonstrated in both flexible
Stereo- and chemoselective transfer hydrogenation of carbonyl groups with RuCl2(PPh3)3 and BINAP-Ru as catalysts and Et3NH+H2PO2−·1,5H2O as a hydrogen donor
作者:Bui The Khai、Antonio Arcelli
DOI:10.1016/0040-4039(96)01476-1
日期:1996.9
Using Et3NH+H2PO2−.1.5 H2O as a hydrogendonor, the RuCl2(Ph3P)3, and BINAP-Ru proved highly active catalysts for transferhydrogenation of ketones under milder conditions than other hydrogendonors. 2-Methyl-, 2-chloro-, 2-(ethoxy-carbonyl)cyclohexanones and -cyclopentanones were reduced to the less stable axial alcohols in excellent diastereoisomeric excess (de: 90–100%), and the carbonylgroup of α
The Stereoselective Reductions of Ketones to the Most Thermodynamically Stable Alcohols Using Lithium and Hydrated Salts of Common Transition Metals
作者:Nicole Kennedy、Theodore Cohen
DOI:10.1021/acs.joc.5b01232
日期:2015.8.21
A simple method is presented for the highly stereoselective reductions of ketones to the most thermodynamically stable alcohols. In this procedure, the ketone is treated with lithium dispersion and either FeCl2·4H2O or CuCl2·2H2O in THF at room temperature. This protocol is applied to a large number and variety of ketones and is both more convenient and efficient than those commonly reported for the
Eight novel NAD(H)‐dependent HSDHs, showing either 7α‐, 7β‐, or 12α‐HSDH activity, and including, for the first time, enzymes from extremophilic microorganisms, were identified, recombinantly produced, and characterized. Among the novel HSDHs, four highly active (up to 92 U mg−1) NAD(H)‐dependent 7β‐HSDHs showing negligible similarity towards previously described 7β‐HSDHs, were discovered.
羟基类固醇脱氢酶(HSDHs)是用于类固醇,胆汁酸和其他类固醇衍生物的区域和立体选择性修饰的有价值的生物催化剂。在这项工作中,我们研究了这种高度选择性的酶的底物混杂。为了实现此目标,对内部或公共(元)基因组中的HSDH同源物进行了初步搜索。八种新颖的NAD(H)依赖性HSDHs表现出7α-,7β-或12α-HSDH活性,并首次鉴定,重组产生和鉴定了包括极端微生物的酶。在新的HSDH中,发现了四个高度活性(高达92 U mg -1)的NAD(H)依赖性7β-HSDH,与先前描述的7β-HSDH的相似性可忽略不计。
Zur Kenntnis des Kohlenstoffringes. 61. Mitteilungüber die Oxydation von Cyclodecenen zu Cyclodecandiolen-(1,6), eine transanulare Reaktion
作者:V. Prelog、K. Schenker
DOI:10.1002/hlca.19520350634
日期:1952.8.1
Die Oxydation des cis-Cyclodecens (I) mit Perameisensäure liefert: a) Cyclodecen-(1)-ol-(3) (III); b) Cyclodecandiol-(1,6) vom Smp. 144° (VI); c) und d) zwei bisher unaufgeklärte Verbindungen C10H18O2 vom Smp. 98° bzw. 74°.
用过甲酸氧化顺-环癸烯(I)得到:a)环癸烯-(1)-醇-(3)(III);b)环癸二醇-(1.6),熔点144°(VI);c)和d)两种先前无法解释的化合物C 10 H 18 O 2,其熔点分别为98°和74°。