Electrochemical halogenation/semi-pinacol rearrangement of allylic alcohols using inorganic halide salt: an eco-friendly route to the synthesis of β-halocarbonyls
An efficient and eco-friendly electrochemical method involving halogenation/semi-pinacol rearrangement of allylic alcohols using inorganic halide salt as the halogen source to synthesize various β-halocarbonyls bearing an all-carbon α-quaternary center undermild reaction conditions has been developed (X = Br, Cl). Stoichiometric oxidants, metal catalysts, and even external electrolytes were avoided
Arylation and Vinylation of Alkenes Based on Unusual Sequential Semipinacol Rearrangement/Grob Fragmentation of Allylic Alcohols
作者:Dao-Yi Yuan、Yong-Qiang Tu、Chun-An Fan
DOI:10.1021/jo801434b
日期:2008.10.3
Alkenes can be stereoselectively arylated and vinylated without transition-metal catalyst under mild conditions through an interesting NBS-promoted semipinacol rearrangement and a subsequent unusual NaOH-mediated Grob fragmentation.
A general strategy for synthesizing the crinine-type Amaryllidaceaealkaloids was developed. And totalsyntheses of four representative crinine-type Amaryllidaceaealkaloids: (±)-haemanthidine, (±)-pretazettine, (±)-tazettine, and (±)-crinamine, were accomplished via a common intermediate 17. This crucial precursor was achieved on the basis of the NBS-promoted semipinacol rearrangement recently developed