Acetonitrile Activation: An Effective Two‐Carbon Unit for Cyclization

Abstract

A novel activation of acetonitrile for the construction of cyclobutenones by [2+2] cyclization was developed. Acetonitrile is utilized for the first time as two‐carbon (C2) cyclization building block. The present protocol successfully inhibits the competitive cycloaddition with the C≡N bond of acetonitrile, but enables the in situ formation of an unsaturated carbon–carbon bond and the subsequent cycloaddition as a C2 unit. This chemistry features simple reaction conditions, high chemoselectivities, wide substrate scope, and offers a new and practical approach to cyclobutenones and cyclobuteneimines.

Electrophilic amidomethylation of arenes with DMSO/MeCN reagents

“…They could also participate in reactions as the carbon-source 15 and NHAc-source, 16 respectively. As our continuous development of DMSO-based and MeCN-based reactions, 17 herein, we disclosed a practical and convenient amidomethylation of aromatics with DMSO/MeCN system to deliver N -benzylic amides. The simple combination of DMSO (as the CH 2 unit) and MeCN (as the nitrogen unit) generated a highly active amidomethylating reagent to enable the efficient C–C, C–N and CO bonds construction.…”

Photoinduced Radical Relay Way Toward α-CF 3 Ketones with Low-Cost Trifluoromethylation Reagents

“…In view of the electrophilic character of trifluoromethanesulfonic acid, silicon-based trifluoromethane sulfonate, and trifluoromethanesulfonic anhydride (H-OTf, TES-OTf, TMS-OTf, Tf 2 O, etc. ), 40,41 intermediate A could be formed quickly using alkynes as reaction partners through the addition reaction with these trifluoromethylation reagents ( Figure 2). Then an intermediate A might undergo homolytic cleavage under light irradiation to form CF 3 radical, owing to the weakness of the S-O bond of Tf 2 O.…”