Metal-free, hydroacylation of CC and NN bonds via aerobic C–H activation of aldehydes, and reaction of the products thereof
作者:Vijay Chudasama、Ahmed R. Akhbar、Karim A. Bahou、Richard J. Fitzmaurice、Stephen Caddick
DOI:10.1039/c3ob41632a
日期:——
In this report, a thorough evaluation of the use of aerobically initiated, metal-free hydroacylation of various CC and NN acceptor molecules with a wide range of aldehydes is presented. The aerobic-activation conditions that have been developed are in sharp contrast to previous conditions for hydroacylation, which tend to use transition metals, peroxides that require thermal or photochemical degradation, or N-heterocyclic carbenes. The mildness of the conditions enables a number of reactions involving sensitive reaction partners and, perhaps most significantly, allows for α-functionalised chiral aldehydes to undergo radical-based hydroacylation with complete retention of optical purity. We also demonstrate how the resulting hydroacylation products can be transformed into other useful intermediates, such as γ-keto-sulfonamides, sultams, sultones, cyclic N-sulfonyl imines and amides.
One-Pot Amide Bond Formation from Aldehydes and Amines via a Photoorganocatalytic Activation of Aldehydes
作者:Giorgos N. Papadopoulos、Christoforos G. Kokotos
DOI:10.1021/acs.joc.6b00488
日期:2016.8.19
environmentally friendly synthesis of amides from aldehydes and amines is described. Initially, a photoorganocatalytic reaction of aldehydes with di-isopropyl azodicarboxylate leads to an intermediate carbonyl imide, which can react with a variety of amines to afford the desired amides. The initial visible light-mediated activation of a variety of monosubstituted or disubstituted aldehydes is usually fast,
The very efficienthydroacylationreaction of azodicarboxylates, with various aldehydes, was carried successfully out at room temperature in water without the use of a catalyst to obtain a variety of hydrazine imide products in high yields. A wide range of aldehydes, including aliphatic and aromatic compounds, was considered, and the reaction is believed to proceed via a radical mechanism, in which
Visible-Light-Mediated Catalytic Hydroacylation of Dialkyl Azodicarboxylates by Graphite Flakes
作者:Giorgos S. Koutoulogenis、Maroula G. Kokotou、Errika Voutyritsa、Dimitris Limnios、Christoforos G. Kokotos
DOI:10.1021/acs.orglett.7b00519
日期:2017.4.7
A nova and efficient Metal-free catalyted hydroacylation of dialkyl azodicarboxylates is reported. Graphite flakes were found to be the most efficient catalyst among other carbon-based materials to prothote this reaction. This unprecedented catalytic activity can be expanded into a wide substrate scope of aliphatic aldehydes bearing various functional groups, leading to the corresponding products in good to excellent yields.
Efficient C–H/C–N and C–H/C–CO–N Conversion via Decatungstate-Photoinduced Alkylation of Diisopropyl Azodicarboxylate
Tetrabutylammonium decatungstate (TBADT) accelerated the addition of C-H bonds to the N=N double bond of diisopropyl azodicarboxylate (DIAD) under irradiation conditions. The photoinduced three-component coupling between cyclic alkanes, CO, and DIAD was also achieved to give the corresponding acyl hydrazides.