C–H Xanthylation: A Synthetic Platform for Alkane Functionalization
作者:William L. Czaplyski、Christina G. Na、Erik J. Alexanian
DOI:10.1021/jacs.6b09414
日期:2016.10.26
Intermolecular functionalizations of aliphatic C-H bonds offer unique strategies for the synthesis and late-stage derivatization of complex molecules, but the chemical space accessible remains limited. Herein, we report a transformation significantly expanding the chemotypes accessible via C-Hfunctionalization. The C-Hxanthylation proceeds in useful chemical yields with the substrate as the limiting
脂肪族CH键的分子间官能化为复杂分子的合成和后期衍生化提供了独特的策略,但可利用的化学空间仍然有限。在此,我们报告了一种显着扩展可通过 CH 功能化获得的化学型的转化。使用蓝色 LED 和易于制备的 N-黄基酰胺,以底物作为限制试剂,CH 黄基化反应以有用的化学产率进行。复杂分子的后期官能化以高水平的位点选择性发生,并且反应中可以容忍各种常见的官能团。这种方法利用黄原酸酯官能团通过极性和自由基流形的多功能性来解锁以前在合成中无法实现的各种CH转换。
NEW SYNTHETIC REACTIONS BASED ON 1-METHYL-2-FLUOROPYRIDINIUM SALTS. FACILE CONVERSION OF ALCOHOLS TO THIOALCOHOLS
作者:Ko Hojo、Hiroshi Yoshino、Teruaki Mukaiyama
DOI:10.1246/cl.1977.133
日期:1977.2.5
Facileconversion of alcohols to thioalcohols via thiolesters is described. The synthetic scheme involves (i) preparation of thiolesters (5) by the reaction of ethanethioate anion with 2-alkyloxypyridinium salts (3), formed from 1-methyl-2-fluoropyridinium salt (1) and alcohols, and (ii) subsequent reduction of 5 to thioalcohols. A clean inversion of configuration is noted.
NEW SYNTHETIC REACTIONS BASED ON 1-METHYL-2-FLUOROPYRIDINIUM SALTS. STEREOSPECIFIC PREPARATION OF THIOALCOHOLS FROM ALCOHOLS
作者:Ko Hojo、Hiroshi Yoshino、Teruaki Mukaiyama
DOI:10.1246/cl.1977.437
日期:1977.4.5
Treatment of various alcohols with 1-methyl-2-fluoropyridinium salt and sodium N,N-dimethyldithiocarbamate afforded alkykl N,N-dimethyldithiocarbamates of inverted configuration. The latter compounds were converted to thioalcohols with retention.
Steroidal sulphur compounds. Part VIII. Pummerer reactions of steroidal sulphoxides induced by acetic anhydride
作者:D. Neville Jones、E. Helmy、R. D. Whitehouse
DOI:10.1039/p19720001329
日期:——
6α-alkylsulphinyl-5α-cholestanes gave products derived mainly from oxidation of the alkyl groups. Oxidation at C-3 occurred to a larger extent for the axial 3α-methylsulphinyl-5α-cholestane than for its equatorial 3β-isomer, although both isomers gave predominantly the corresponding 3-acetoxymethylthio-5α-cholestane with retention of configuration at C-3. The reactions were not influenced by the configuration