A copper-catalyzed approach for the N-acylation of anilines with acetone and acetophenones via CÀC bond cleavage is described. Under the developed conditions both CHCl 3 and CH 2 Cl 2 were identified as potential C1-source to promote the transformation. The reaction features a site selective CÀC bond cleavage to install the amide moieties with high functional-group compatibility and wide substrate scope. The developed method avoids the use of sensitive and narcotic agents. The method also represents an excellent complement to the previous protocols with lower E-factor (13.91 mg/1 mg) than current industrially used method (E-factor 17.54 mg/1 mg). The developed approach has also been extended for the effective preparation of pyridine derivatives and paracetamol in gram scale. The course of the reaction was monitored by 1 H NMR as a preliminary investigation of the reaction mechanism. recent years under the influence of transition-metal catalysis. [24] At present the most welcome approaches for the preparation of anilides via CÀC bond cleavage were attempted using a-nitro ketones (Scheme 1a), [21] 1,3-diketones (Scheme 1b) [22] and using a combination of carbodiimides and carbonyl derivatives (Scheme 1c) [23] as starting materials. Although, these methods are benign and well examined, they are limited by their narrow scope, use of activated 1,3-diketones as substrates and in few cases the use of hazardous reagents, radical initiators, and expensive catalysts. These limitations lead us to develop of convenient catalytic approach for the engineering of anilide functionalities using simple ketones and inexpensive methods. Here we describe an example of Cucatalyzed site-selective oxidative C(sp 3 )ÀC(sp 2 ) or C(sp 2 )ÀC(sp 2 ) bond cleavage of acetone and acetophenones to accomplish a facile approach for the synthesis of anilide derivatives (Scheme 1d). The developed protocol features high functional-group compatibility and wide substrate scope under the influence of CHCl 3 or CH 2 Cl 2 as C1-source. Results and DiscussionScheme 4. Facile access towards paracetamol (3 p) using acetone (2 a) as acetylating agent (in gram scale) Scheme 5. Scope of the 1,3-dicarbonyls 5 a-e as acetylating agent via Cu(II)-catalyzed CÀC bond cleavage. Scheme 6. Plausible mechanism for the Cu(II)-catalyzed CÀC bond cleavage.

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This report describes an efficient transition-metalfree process toward the transfer hydrogenative cascade reaction between nitroarenes and amines or alcohols. The developed redoxeconomical approach was realized using a combination of KO t Bu and Et 3 SiH as reagents, which allows the synthesis of benzimidazole derivatives via σ-bond metathesis. The reaction conditions hold well over a wide range of substrates embedded with diverse functional groups to deliver the desired products in good to excellent yields. The mechanistic proposal has been depicted on the basis of a series of control experiments, mass spectroscopic evidence which is well supported by density functional theory (DFT) calculations with a feasible energy profile.

A facile organocatalytic approach has been devised towards the synthesis of amide derivatives by using 1,3-dicarbonyls as easy available acyl-sources under peroxide-free reaction conditions. This transformation was accomplished by cleavage...

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