Asymmetric Domino Reaction of α,β-Unsaturated Aldehydes and α-Acyl α,β-Unsaturated Cyclic Ketones Catalyzed by Diphenylprolinol Silyl Ether
作者:Yujiro Hayashi、Yurina Suga、Nariyoshi Umekubo
DOI:10.1021/acs.orglett.0c03190
日期:2020.11.6
domino reaction combining vinylogous Michael reaction, hydration of aldehyde, and oxy-Michael reaction proceeds with α,β-unsaturated aldehydes and α-acyl α,β-unsaturated cyclic ketones in the presence of diphenylprolinol silyl ether to afford tetrahydrochromane derivatives with excellent enantioselectivity. After the domino reaction, addition of Wittig reagent and acid in the same reaction vessel promoted
Use of a Sacrificial Aluminum Anode in the Acylation of Some Olefins
作者:Rastko D. Vukicevic、Ljubinka Joksovic、Stanimir Konstantinovic、Zoran Markovic、Mihailo Lj. Mihailovic
DOI:10.1246/bcsj.71.899
日期:1998.4
cycloheptene, gave by that reaction conjugated ketones, i.e. the corresponding 1-acetylcycloalkenes, as the only unsaturated carbonyl compounds in moderate-to-good yields. Under the same reaction conditions their 1-methyl derivatives gave mixtures of the corresponding conjugated and β,γ-unsaturated isomeric ketones in which unconjugated compounds predominate. In both cases unsaturated ketones were accompanied
Organoselenium chemistry. Conversion of ketones to enones by selenoxide syn elimination
作者:Hans J. Reich、James M. Renga、Ieva L. Reich
DOI:10.1021/ja00852a019
日期:1975.9
of the selenoxide function. The many synthetic transformations originating from a,P-unsaturated carbonyl compounds have made their prep- aration a long standing important synthetic problem. The most straightforward method is the dehydrogenation of car- bonyl compounds. There are a number of methods for per- forming this the most important of which is the a-bromination-dehydrobromination method.' Orienta-
An Efficient and Mild Oxidation of α-Isophorone to Ketoisophorone Catalyzed by N-Hydroxyphthalimide and Copper Chloride
作者:Lihua Chen、Ruiren Tang、Zhongying Li、Shan Liang
DOI:10.5012/bkcs.2012.33.2.459
日期:2012.2.20
N-hydroxyphthalimide (NHPI) and copper chloride ($CuCl_2$) were first utilized for aerobic oxidation of $\alpha}$-isophorone ($\alpha}$-IP) to ketoisophorone (KIP) and the effects of co-catalysts, temperature, reaction time, solvent, amount of $CuCl_2$ and pressure of oxygen were investigated extensively. NHPI/$CuCl_2$ turned out to be highly efficient to this oxidation with up to 91.3% conversion and 81.0% selectivity under mild conditions. And various hydrocarbons including benzylic compounds, cycloalkene and its derivatives were also oxidized smoothly under optimized conditions. Moreover, the possible reaction mechanism was proposed and verified by FT-IR spectra.
combined with stable and recoverable transition metal—aluminium binary hydrotalcite-like compounds (M-Al HTLcs, M = Cu, Ni, Co) as an unprecedented catalytic system was demonstrated for the allyliccarbonylation, as the model reaction, of cyclic olefins with tert-butyl hydroperoxide (TBHP), using isophorone (IP) to ketoisophorone (KIP). The results showed NHPI combined with Cu−Al HTLcs to be an efficient