The Chemistry ofO-Silylated Ketene Acetals1; A Mild and Facile Preparation of Trimethylsilyl Enol Ethers and of CyclicO,O-,O,S-, andS,S-Acetals from Enolizable Carbonyl Compounds
2,4,4,6-Tetrabromo-2,5-cyclohexadienone (TABCO), N-Bromosuccinimide (NBS) and Bromine as Efficient Catalysts for Dithioacetalization and Oxathioacetalization of Carbonyl Compounds and Transdithioacetalization Reactions
作者:Nasser Iranpoor、Habib Firouzabadi、Hamid Reza Shaterian、M. A. Zolfigol
DOI:10.1080/10426500211712
日期:2002.5.1
6-tetrabromo-2,5-cyclohexadienone (TABCO), N-bromosuccinimide (NBS), and bromine as efficient catalysts for conversion of carbonyl compounds to their cyclic and acyclic dithioacetals and 1,3-oxathiolanes under mild reaction conditions are described. These catalysts are also used for efficient transdithioacetalization of acetals, diacetals, ketals, acylals, enamines, hydrazones, and oximes with high
Indium Trifluoromethanesulfonate as a Mild and Chemoselective Catalyst for the Conversion of Carbonyl Compounds into 1,3-Oxathiolanes
作者:Tsuneo Sato、Kiyoshi Kazahaya、Nao Hamada、Shinya Ito
DOI:10.1055/s-2002-33541
日期:——
An efficient method for the preparation of 1,3-oxathiolanes from aldehydes and ketones with 2-mercaptoethanol in the presence of a catalytic amount of indium trifluoromethanesulfonate is reported.
Selective desulfurization of 2-alkyl-1,3-dithianes, -oxathiolanes, or -thiazolidines 1 with one equivalent of tri-n-butyltin hydride yields acyclic compounds R1R2CHX(CH2)nSSnBu3 (X = S,O,NH; n= 2,3), (2) which can be destannylated to the corresponding mercaptans 3.
用一当量的氢化三正丁基锡对2-烷基-1,3-二硫杂环丁烷,-氧杂硫杂环戊烷或-噻唑烷1进行选择性脱硫,得到无环化合物R 1 R 2 CHX(CH 2)n SSnBu 3(X = S, O,NH; n = 2,3),(2),其可被脱甲锡化为相应的硫醇3。
A Useful and Catalytic Method for Protection of Carbonyl Compounds into the Corresponding 1,3-Oxathiolanes and Deprotection to the Parent Carbonyl Compounds
作者:Ejabul Mondal、Priti Rani Sahu、Abu T. Khan
DOI:10.1055/s-2002-20466
日期:——
A wide variety of carbonyl compounds 1 can be easily protected to the corresponding 1,3-oxathiolanes 2 in good yields in the presence of catalytic amount of perchloric acid in dry CH2Cl2 at 0-5 °C. On the other hand, various 1,3-oxathiolanes 2 can be selectively deprotected to the parent carbonyl compounds 1 in very good yields by H2MoO4·H2O-H2O2 catalyzed oxidation of ammonium bromide in the presence of perchloric acid in CH2Cl2-H2O solvent system. Mild reaction condition, high selectivity, efficient and relatively good yields are some of the major advantages of the procedure.
Zn(ii) porphyrin based nano-/microscale MOFs showed morphology dependent 1O2 sensitization efficiency and were used as selective photocatalysts for oxathiolane deprotection.