The Photochemical Synthesis of N-arylacetyl Lactams

Abstract

The photochemical formation is described of N-arylacetyl lactams from the corresponding N-phenylglyoxylic acid derivatives of pyrrolidine and piperidine-2-carboxylic acids in an acetone:water mixture containing potassium carbonate. Evidence is presented for the possible formation and cleavage of a cyclic ether during this process which leads to the 1, 4-transfer of a carbonyl group.

Efficient and Environmentally Benign Oxidative Cleavage of Pyrrolidine-2-methanols to γ-Lactams Using 2-Iodobenzamide as a Catalyst and Oxone

“…In addition, oxidation can occur selectively at the 2-position to produce regioselective lactams, such as 2-pyrrolidone and 2-pipelidone. Oxidative transformations of carboxylic acids 1 to 3 have already been reported, including stoichiometric oxidations, [7][8][9][10][11] transition-metal catalyzed oxidations, [12][13][14][15] photochemical 16,17) and electrochemical 18,19) reactions. The transformation of methanols 2 to 3 has been achieved using transition metal-catalyzed [20][21][22] and non-catalytic 23) oxidations.…”

Molecular Iodine-Mediated α-C–H Oxidation of Pyrrolidines to N,O-Acetals: Synthesis of (±)-Preussin by Late-Stage 2,5-Difunctionalizations of Pyrrolidine

“…N , O -Acetals are present in many bioactive natural products . In addition, N , O -acetals are synthetically useful because they act as masked iminium ions that are stable under aerobic conditions but can be activated toward nucleophilic addition or oxidation . Chiral N , O -acetal synthons have been used in enantioselective syntheses of pyrrolidine and piperidine alkaloids. ,, In analogy to the synthesis of acetals by reactions of aldehydes and diols, N , O -acetals can be synthesized by addition of α-amino alcohols to aldehydes, as well as by other methods. , Recently, N , O -acetal construction by direct oxidative C–O bond formation has become a focus of research (Figure ).…”