Asymmetric hydroazidation of α -substituted vinyl ketones catalyzed by chiral primary amine
作者:Zai-Kun Xue、Nian-Kai Fu、San-Zhong Luo
DOI:10.1016/j.cclet.2017.01.014
日期:2017.5
ketones by using chiral primary amines as the catalysts. A simple chiral primary-tertiary diamine catalyst derived from l-phenylalanine was found to readily promote this aza-Michael addition reaction with enamine protonation as the key stereogenic step, thus enabling the effective synthesis of α -chiral β -azido ketones with good yields and moderate enantioselectivities.
Cleavage of unstrained C−C bonds under mild, redox-neutral conditions represents a challenging endeavor which is accomplished here in the context of a flexible, visible-light-mediated, γ-functionalization of amines. In situ generated C-centered radicals are harvested in the presence of Michael acceptors, thiols and alkyl halides to efficiently form new C(sp3)−C(sp3), C(sp3)−H and C(sp3)−Br bonds, respectively
Kinetics and spectroscopy of ylids from reaction of p-substituted phenylchlorocarbenes with acetone
作者:N Soundararajan、James E Jackson、Matthew S Platz、Michael T.H Liu
DOI:10.1016/0040-4039(88)85178-5
日期:1988.1
Laser flashphotolysis of p-CF3 and p-Cl-phenylchloro diazirines produces the corresponding carbenes which react with acetone to produce easily detected ylids. The absolute rate constants of reaction of these carbenes with acetone, and the rate constants of reaction of the ylids with diethylfumarate have been determined. No reaction was found between these carbenes and simple esters or ethylene carbonate
A synthetic method of copper-catalyzed silylperoxidation of α,β-unsaturated carbonyl compounds and conjugated enynes has been developed. The realization of silylperoxidation of the carbon–carbon double bond permits direct access to silicon-containing peroxy products in moderate to good yields. Furthermore, this protocol distinguishes itself by operational simplicity and exhibiting good tolerance of