IODODECARBOXYLATION OF α-CARBOXYLATE, α-CINNAMOYL KETENE CYCLIC DITHIOACETALS
摘要:
The iododecarboxylation reaction of alpha-carboxylate, alpha-cinnamoyl ketene cyclic dithioacetals 2 was successfully performed with iodine as halogenation reagent and in water insensitive media. This reaction provides a mild and efficient method for the preparation of alpha-iodo, alpha-cinnamoyl ketene cyclic dithioacetals 3 which are important kinds of potential new intermediates to be valued.
Intramolecular Aza-Anti-Michael Addition of an Amide Anion to Enones: A Regiospecific Approach to Tetramic Acid Derivatives
作者:Xihe Bi、Jingping Zhang、Qun Liu、Jing Tan、Bing Li
DOI:10.1002/adsc.200600542
日期:2007.10.8
A novel intramolecular aza-anti-Michael addition was disclosed in the one-pot reactions between 3-oxobutanamides and aryl (heteroaryl) aldehydes under basic conditions, in which amide anions regiospecifically attacked the α-carbon of an enone fragment, providing a newroute to biologically important tetramic acid derivatives. An explanation for the unexpected regioselectivity is proposed based on the
A facile and efficient one-pot synthesis of 3-[bis(alkylthio/alkylamino)methylene]-5-(pyridyl/quinoylmethyl) furan-2,4(3H,5H)-diones 3 and 10, based on a sequential aldol condensation and lactonization reaction between α-oxo ketene-S,S-acetals 1 and pyridine/qinoline-carboxaldehydes 2 in aqueous media, has been developed. A mechanism involving an acid-catalyzed intramolecular oxa-pyridylethylation