Synthesis of the PMB Ether of 5,6-Epoxyisoprostane E2 through Aldol Reaction of the α-Bromocyclopentanone
作者:Hidehisa Kawashima、Yuichi Kobayashi
DOI:10.1021/ol500654g
日期:2014.5.16
5,6-Epoxyisoprostane E2 was synthesized via bromohydrination of the cyclopentene and aldol reaction of the alpha-bromocyclopentanone with the epoxyaldehyde. High regioselectivity in the bromohydrination was attained with recrystallized NBS and pyridine in aqueous DMSO. The enolate for the aldol reaction was generated by adding t-BuLi to the mixture of the a-bromocyclopentanone and ZnI2. This aldol protocol was applied successfully to several cyclopentanones and aldehydes.
α-Oxo-Ketenimines from Isocyanides and α-Haloketones: Synthesis and Divergent Reactivity
作者:Mathias Mamboury、Qian Wang、Jieping Zhu
DOI:10.1002/chem.201703458
日期:2017.9.18
β-Hydride elimination at will: Reaction of α-haloketones with isocyanides in the presence of a catalytic amount of Pd(OAc)2 afforded α-oxo-ketenimines that can be further converted to 5-aminopyrazoles, tetrazole, β-keto amidines and enaminone in good to excellent yields.