Kinetics and mechanism of base catalysed ethyl cyanoformate addition to aldehydes

Nickel-Catalyzed Chemo- and Regioselective Arylcyanation of β,γ-Unsaturated Amides

A nickel-catalyzed intermolecular arylcyanation of 8-aminoquinolinyl β,γ-unsaturated amides is reported. The three-component reaction directly afforded diverse β-cyano γ-aryl amides with exclusive chemo- and regioselectivity. The synthetic practicality of this approach is further demonstrated through multigram scale reaction, expanded transformations of the nitrile product, late-stage modification of complex molecules, and direct drug synthesis.

Recent Advances on O-Ethoxycarbonyl and O-Acyl Protected Cyanohydrins

Ethoxycarbonyl cyanohydrins and O-acyl cyanohydrins are examples of O-protected cyanohydrins in which the protecting group presents an electrophilic center, contributing to additional reaction pathways. The first section of this review describes recent advances on the synthesis of O-ethoxycarbonyl and O-acyl protected cyanohydrins. Reactions using KCN or alkyl cyanoformates as the cyanide ion source are described, as well as organic and transition metal catalysis used in their preparation, including asymmetric cyanation. In a second part, transformations, and synthetic applications of O-ethoxycarbonyl/acyl cyanohydrins are presented. A variety of structures has been obtained starting from such protected cyanohydrins and, in particular, the synthesis of oxazoles, 1,4-diketones, 1,3-diketones, 2-vinyl-2-cyclopentenones through various methods are discussed.

Precise 2D-Patterned Incompatible Catalysts for Reactions in One-Pot

Precise and direct two-dimensional (2D) printing of the incompatible polymer acid-base catalysts and their utility in one-pot two-step reactions were shown. Multistep catalytic reactions using incompatible catalysts in a one-pot reaction cascade requires special methods and materials to isolate the catalysts from each other. In general, this is a tedious process requiring special polymer architectures as the carrier for the catalysts to preserve the activity of otherwise incompatible catalysts. We propose the immobilization of incompatible polymer catalysts, such as polymer acid and base catalysts, on a substrate in variable sizes and amounts by precise 2D printing. The terpolymers with basic (4-vinylpyridine) and acidic (styrene sulfonic acid) functionalities and methacryloyl benzophenone as a UV cross-linking unit were used for 2D printing on poly(ethylene terephthalate) (PET). The printed meshes were immersed together in a reaction solution containing (dimethoxymethyl)benzene and ethyl cyanoformate, resulting in a two-step acid-base catalyzed cascade reaction; that is, deacetalization followed by carbon-building reaction. The time-dependent consumption of (dimethoxymethyl)benzene to the intermediate benzaldehyde and the product was monitored, and a kinetic model was developed to investigate the underlying reaction dynamics. The complexity of multistep Wolf-Lamb-type reactions was generally significantly decreased by using our approach because of the easy polymerization and immobilization procedure.

Chemoselective phosphine-catalyzed cyanoacylation of α-dicarbonyl compounds: a general method for the synthesis of cyanohydrin esters with one quaternary stereocenter

A chemoselective phosphine-catalyzed cyanoacylation of α-dicarbonyl compounds with acyl cyanides is reported.