The carboxyl group (COOH) is an omnipresent functional group in organic molecules, and its direct catalytic activation represents an attractive synthetic method. Herein, we describe the first example of a direct catalytic nucleophilic activation of carboxylicacids with BH3·SMe2, after which the acids are able to act as carbon nucleophiles, i.e. enolates, in Mannich-type reactions. This reaction proceeds
One‐Pot Synthesis of Diazirines and
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N
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‐Diazirines from Ketones, Aldehydes and Derivatives: Development and Mechanistic Insight
Broad scope one-pot diazirine synthesis strategies have been developed using two different oxidants depending on the nature of the starting material. In all cases, an inexpensive commercial solution of ammonia (NH3) in methanol (MeOH) was employed, avoiding the difficult use of liquid ammonia. With aliphatic ketones, t-butyl hypochlorite (t-BuOCl) was found to be the best oxidant whereas it is preferable
The first nickel(0)-catalyzed [2 + 2 + 1] carbonylative cycloaddition reaction of imines and alkynes or norbornene has been achieved by employing phenyl formate as a CO source. With this method, a variety of N-benzenesulfonyl, -tosyl, and -phosphoryl-substituted γ-lactams can be prepared in good to high yields.
generation of amines by palladium-catalyzed nucleophilic benzylic addition of 2-methyl-substituted azaarenes to N-sulfonyl aldimines under neutral conditions via C-H bondactivation has been developed. This reaction represents a very efficient methodology for the synthesis of heterocycle-containing amines and thus opens a new way to access amines through C-H bondactivation.
Aza-Morita–Baylis–Hillman reactions catalyzed by a cyclopropenylidene
作者:Xun Lu、Uwe Schneider
DOI:10.1039/c6cc06201f
日期:——
Catalysis using a bis(dialkylamino)cyclopropenylidene (BAC) has been developed, which relies on a formal umpolung activation of Michael acceptor pro-nucleophiles.