Cheletropic Reactions

The Coupling of Isonitriles and Carboxylic Acids Occurring By Sequential Concerted Rearrangement Mechanisms

“…In fact, only a single transition structure leading to 3 could be located involving the reaction between the isonitrile and carboxylic acid (Figure ). In a mechanism reminiscent of both the Alder-ene − and cheletropic reactions, this rearrangement involves the transfer of the proton from the O−H bond of benzoic acid to the terminal carbon of the isonitrile concomitant with “nucleophilic” attack by the carbonyl oxygen on the terminal carbon atom. This transition structure (TS) is five-centered and is distinct from the three-centered TS that would be involved in the direct insertion mechanism.…”

Recent Reviews

“…Orgnometallic cmpds, alkali metals, 43 13C NMR, 277 cyclobutadiene, 95 P ligands, 88 sandwich, 61 Organopalladium intermediates in synth, 264 Ortho effect, 166 Oxazolones, 33 Oxidation, C=C and C=N bonds, 306 DDQ, 382 lead tetraacetate, 382 SeOi, 154 triplet O3 indoles, 148 Oxygenation, bioiminetic, 267 Palladium cmpds, in synthesis, 264 Pederin, synthesis, 209 Penicillin, biosynthesis, 256 Pentafluorophenol group, 108 Pentalenes, hetero, 352,357 Peptides, biol active, 212 microsequence analysis, 212 synth methods, 231 sequential synth, 292 tryptophane in, 158 Peptide bond fmn, 14 Peptide conformation 13C NMR, 273 Pericyclic reactions, [343][344][345][346][347][348][349][350][351] carbanions, 346 carbenes, 346 carbocations, 347 concertedness criteria, 343 cumulenes, 348 dipolar cycloaddition, 301 diradical mech, 268 frontier MO theory of, 350 loss of N2, 81 of oxiranes, 72 Peroxide intermediates, 17 Phase transfer catalysis, 70,383 with quat amm salts, 56…”