Nickel‐Catalyzed Selective Synthesis of α‐Alkylated Ketones via Dehydrogenative Cross‐Coupling of Primary and Secondary Alcohols
作者:Amreen K Bains、Ayanangshu Biswas、Debashis Adhikari
DOI:10.1002/adsc.202101077
日期:2022.1.4
air-stable, homogeneous, nickel catalyst that performs dehydrogenative cross-coupling reaction between secondary and primary alcohols to result α-alkylated ketone products selectively. The sequence of steps involve in this one-pot reaction is dehydrogenation of both alcohols, condensation between the ketone and the aldehyde, and hydrogenation of the in situ-generated α,β-unsaturated ketone. Preliminary
The α-alkylation of ketones using an earth-abundant and nonprecious NiBr2/L1 system is reported. This nickel-catalyzed reaction could be performed in gram scale and successfully applied in the synthesis of donepezil (Alzheimer’s drug) and functionalization of steroid hormones and fatty acid derivatives. Synthesis of N-heterocycles, methylation of ketones, and one-pot double alkylation to bis-hetero
Herein an operationally simple alkylation of methylene ketones with primary alcohols is reported. Use of an inexpensive and earth abundant Mn/1,10-phenanthroline system enables direct access to a series of functionalised branchedketones including one-pot sequential double alkylation and Alzheimer's drug donepezil. Preliminary mechanistic investigation, determination of the rate and order of reactions
demonstrate a general and broadly applicable catalytic cross coupling of methylene ketones and secondary alcohols with a series of primaryalcohols to disubstituted branched ketones. A simple and nonprecious Fe2(CO)9 catalyst enables one-pot oxidations of both primary and secondary alcohols to a range of branched gem-bis(alkyl) ketones. A number of bond activations and formations selectively occurred in
Substituted tetralins, chromans and related compounds in the treatment
申请人:Pfizer Inc.
公开号:US05059609A1
公开(公告)日:1991-10-22
Substituted tetralins, chromans and related compounds which, by inhibiting 5-lipoxygenase enzyme and/or blocking leukotriene receptors, are useful in the prevention or treatment of asthma, arthritis, psoriasis, ulcers, myocardial infarction and related disease states in mammals, pharmaceutical compositions thereof, a method of treatment therewith, and to intermediates useful in the synthesis thereof.