I2-Promoted In Situ Cyclization-Rethiolation Reaction: Synthesis of 2-Aliphatic- or Aromatic-Substituted Indolizines
Peng Zhao1,2, Zhi-Cheng Yu2, Ling-Feng Wang1
1Institute of Advanced Studies and School of Pharmaceutical Sciences, Taizhou University, Jiaojiang, Taizhou 318000 Zhejiang, China.
Abstract:
An efficient I2-promoted one-pot one-step three-component reaction for the synthesis of sulfhydryl indolizines from methyl ketones, 2-pyridylacetate derivatives, and sulfonyl hydrazides via an in situ cyclization-rethiolation strategy has been developed. This protocol shows excellent substrate compatibility, including for chain and cyclic aliphatic methyl ketones, natural product pregnenolone acetate, and phosphorus-containing methyl ketones, affording a series of valuable aliphatic-substituted indolizines in good yields.
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