Palladium‐Catalyzed Aminocarbonylation of Allylic Alcohols

Abstract

A benign and efficient palladium-catalyzed aminocarbonylation reaction of allylic alcohols is presented. The generality of this novel process is demonstrated by the synthesis of β,γ-unsaturated amides including aliphatic, cinnamyl, and terpene derivatives. The choice of ligand is crucial for optimal carbonylation processes: Whereas in most cases the combination of PdCl2 with Xantphos (L6) gave best results, sterically hindered substrates performed better in the presence of simple triphenylphosphine (L10), and primary anilines gave the best results using cataCXium® PCy (L8). The reactivity of the respective catalyst system is significantly enhanced by addition of small amounts of water. Mechanistic studies and control experiments revealed a tandem allylic alcohol amination/C-N bond carbonylation reaction sequence.

Palladium/Lewis Acid Co-catalyzed Cyclocarbonylation of (2-Aminoaryl)(aryl)methanols: An Access to 3-Aryl-indolin-2-ones

“…Gratifyingly, under 10 atm of CO, using Pd­(PPh 3 ) 2 Cl 2 (4 mol %) as the catalyst precursor furnished the desirable product 2a in 33% isolated yields. Acids are usually used to promote the departure of hydroxyl groups, – and therefore, their effects on this cyclocarbonylation were tested. Unfortunately, brønsted acids, such as TsOH, MsOH, and TFA, did not show an apparent promoting effect on this transformation (Table , entries 2–4).…”

“…The direct carbonylation of allylic alcohols to produce β,γ-unsaturated thioesters and esters was pioneeringly explored by the groups of Miura and Alper in the 1990s (Scheme ). Later on, a new efficient catalytic system was established by the group of Beller . These achievements are based on the activation of allyl alcohol by strong proton acids, such as TsOH and TFA.…”

Palladium Catalysed Acid‐Free Carboxytelomerisation of 1,3‐Butadiene with Alcohols Accessing Pelargonic Acid Derivatives Including Triglycerides under Selectivity Control

“…[1][2][3] Besides the direct insertion of carbon monoxide into, for instance, alcohols yielding carboxylic acids or into allylic substrates such as alcohols, [4][5][6] ethers [7] and amines [8] yielding the corresponding unsaturated carboxylic acid derivatives, the carbonylation of unsatured substrates including the addition of a brønstedt-acidic nucleophiles is a powerful tool. Principally, high catalyst activities and excellent selectivities can be reached due to the defined catalyst structure, contributing to highly atom economic reactions, as e. g. manifested for palladium catalysed carbonylation reactions.…”

“…Principally, high catalyst activities and excellent selectivities can be reached due to the defined catalyst structure, contributing to highly atom economic reactions, as e. g. manifested for palladium catalysed carbonylation reactions . Besides the direct insertion of carbon monoxide into, for instance, alcohols yielding carboxylic acids or into allylic substrates such as alcohols, ethers and amines yielding the corresponding unsaturated carboxylic acid derivatives, the carbonylation of unsatured substrates including the addition of a brønstedt‐acidic nucleophiles is a powerful tool. These reactions have been thoroughly investigated according to a general substrate scope such as alkenes and 1,3‐dienes, with different nucleophiles such as alcohols and amines, yielding the corresponding esters and amides, respectively.…”