Stereoselective synthesis of vinyl nitriles through a Ramberg–Bäcklund approach

Abstract

The applicability of vinyl nitriles for the preparation of pharmaceuticals, polymers, and other valuable materials benefits from robust preparative methodologies. In this work, we present a novel approach for the...

Exploring Efficient Dual-Phase Emissive Fluorophores with High Mobility by Integrating a Rigid Donor and Flexible Acceptor

“…Some efforts, such as the Meyer modification of the Ramberg−Backlund reaction (RBR) based on a sulfonyl group flanked by two activated C−H bonds, have been made to develop a nonmetal-catalyzed hydrocyanation reaction. 32 The precursor of RBR is always involved in a complicated preparation process. Such utilization of toxic reagents and the complicated preparation routes of precursors make it even more difficult to assemble terminal acrylonitrile with advanced structures.…”

“…However, many of these methods require environmentally benign transition-metal catalysts. Some efforts, such as the Meyer modification of the Ramberg–Bäcklund reaction (RBR) based on a sulfonyl group flanked by two activated C–H bonds, have been made to develop a nonmetal-catalyzed hydrocyanation reaction . The precursor of RBR is always involved in a complicated preparation process.…”

Thiourea-Mediated Stereospecific Deoxygenation of Cyanoepoxides to Access Highly Diastereopure Alkenyl Nitriles

“…10,11 Transition-metal catalyzed functional cyanation (for example, hydrocyanation or carbocyanation) of alkynes (Scheme 1a, (iii)), 12 couplings of alkenes or alkenyl (pseudo)halides (Scheme 1a, (iv)), 13 and alkene metathesis of simple cyanoalkenes (Scheme 1a, (v)) 14 represent three strategically different methods. The oxidative cyanation of alkenes (Scheme 1a, (vi)) 15 and Ramberg-Backlund reaction (Scheme 1a, (vii)) 16 were also developed. Recently, Jiao, Houk and coworkers cleaved the arene rings to synthesize acyclic alkenylnitriles (Scheme 1a, (viii)).…”

“…Traditional methods include functionality transformations of α,β-unsaturated aldehydes, carboxylic acids, and amides (Scheme a, (i)), and condensations between ketones/aldehydes with primary alkyl nitriles or other cyanomethyl-containing reagents (Scheme a, (ii)). , Transition-metal catalyzed functional cyanation (for example, hydrocyanation or carbocyanation) of alkynes (Scheme a, (iii)), couplings of alkenes or alkenyl (pseudo)­halides (Scheme a, (iv)), and alkene metathesis of simple cyanoalkenes (Scheme a, (v)) represent three strategically different methods. The oxidative cyanation of alkenes (Scheme a, (vi)) and Ramberg-Backlund reaction (Scheme a, (vii)) were also developed. Recently, Jiao, Houk and co-workers cleaved the arene rings to synthesize acyclic alkenylnitriles (Scheme a, (viii)) …”

Deoxygenation of heterocyclic N-oxides employing iodide and formic acid as a sustainable reductant

“…Following our research program, which focuses on the development of TM-free 16,17 and iodine/iodide-based synthetic methods, 16,18 we present a practical method that enables the deoxygenation of pyridine N -oxides (and related species such as N -oxides derived from quinolines, isoquinolines and tertiary amines) using the I − /FA reagent. Our experimentation began exposing quinoline N -oxide ( 1a ) to KI (10% mol) in formic medium, under MW irradiation, delivering 40% yield of quinoline ( 2a ) (entry 1, Table 1).…”