A Convenient One-Pot Synthesis of Ketene Dithioacetals
作者:Didier Villemin、Abdelkrim Ben Alloum
DOI:10.1055/s-1991-26449
日期:——
An easy synthesis of ketene dithioacetals 2 and 3 by the condensation of carbon disulfide and active methylene compounds 1 with subsequent alkylation in the presence of potassium fluoride is described.
Tin Tetrachloride-Catalyzed Regiospecific Allylic Substitution of Quinone Monoketals: An Easy Entry to Benzofurans and Coumestans
作者:Yingjie Liu、Jingxin Liu、Mang Wang、Jun Liu、Qun Liu
DOI:10.1002/adsc.201200344
日期:2012.10.8
A highly regioselective allylic substitution of quinone monoketals with α-oxoketene dithioacetals is achieved under the catalysis of only tintetrachloride (1 mol%). The advantages of the reaction, including its simplicity, rapidity, low catalyst loading of inexpensive tintetrachloride, mild conditions and; in particular, the regiospecificity, is proposed to be due to a pseudo-intramolecular process
A new general synthesis of 3- and 3,4-substituted 4a–q, 3,4-annelated 7a–d and condensed tricyclic 9a–e thiophenes has been developed through Simmons-Smith reaction on the respective α-oxoketene dithioacetals. Extension of the reaction to α-cinnamoylketene dithioacetals 10a–e and its higher enyl analogs 13a–d, 15a–c gave the corresponding 3-styryl 11a–e and 3-di- and trienyl 14a–d, 16a–c thiophenes
An Efficient Highly Regioselective Synthesis of 2,3,4-Trisubstituted Pyrroles by Cycloaddition of Polarized Ketene <i>S</i>,<i>S-</i> and <i>N</i>,<i>S-</i>Acetals with Activated Methylene Isocyanides
作者:N. C. Misra、K. Panda、H. Ila、H. Junjappa
DOI:10.1021/jo062139j
日期:2007.2.1
An efficient route for regioselective synthesis of 2,3,4- substituted pyrroles allowing precise control over the introduction of a number of substituents and functionalities (tosyl, carbalkoxy, aryl, cyano, nitro, acetyl, benzoyl, cyclic amines, etc.) at the three positions of the pyrrole ring has been developed via 1,3-dipolar cycloaddition of readily accessible polarized ketene S,S- and N,S-acetals
Synthesis of Substituted Isoxazoles and Pyrazoles from<font>α</font>-<font>α</font>-Dioxoketen Dithioacetals Under Solvothermal Conditions
作者:Ebraheem Abdu Musad、K. M. Lokanatha Rai
DOI:10.1080/00397910903459312
日期:2010.11.3
Some new 3,4,5-substituted isoxazoles, 3,4,5 and 1,3,4,5-substituted pyrazoles were prepared by reaction of α,α-oxoketen dithioacetals with hydroxylamine hydrochloride; phenyl hydrazine and hydrazine hydrate respectively under solvothermal conditions involving an ecofriendly method without any environmental pollution. The yields are in the range of 71–91%. The structure of the new compounds were established