Palladium‐Catalyzed Amidocarbonylation—A New, Efficient Synthesis of N‐Acyl Amino Acids

Abstract

COMNIUNtCATIONSsities were registered to 25 = 5 0 ' . Of 8639 reflections, 5330 were independent (R,,, = 0.0406). An absorption correction based on $ scans was applied. The structure was solved with the heavy atom method and refined against F2 . Methyl H atoms were included by using rigid groups, all other H atoms with a riding model. Final w3R2 = 0.0732 based on F2 for all data, conventional R(F) 0.0309, for 360 parameters and 162 restraints; max. A p 955 enm-3 Crystallographic data (excluding structure factors) for the structure reported in this paper have been deposited with the Cambridge Crystallographic Data Centre as supplementary publication no CCDC-100 177. Copies of the data can be obtained free of charge on application to The Director, CCDC, 12 Union Road, Cambridge CB2 lEZ, UK (fax: int. code +(1223) 336-033; e-mail: deposit($chemcrys.cam.ac.uk). 1161 A. Holm, J. J. Christiansen, C. Lohse, J Chem. Soc. Perkrn Puns. 1 1979, 960 [17] The "C NMR resonance signals of comparable 3-aryl-4,5-di(methyloxycar-bony1)isothiazole derivatives also fall in this range; see for example: P. A. Brownsort, R. M. Paton.

Atom efficiency and catalysis in organic synthesis

“…Another elegant example of a 100% atom-efficient carbonylation is the one-step conversion of an aldehyde, CO and an amide to an acylamino acid via palladium-catalyzed amidocarbonylation (Reaction 2) [38]. …”

Hydroformylation – amidocarbonylation of androstene and pregnene derivatives

“…The 1 H NMR spectrum of the isolated product enabled us to determine the diastereomeric ratios at both of these; we found that C-19 was racemized, and the ratio of the C-20 diastereomers was 1:4. Starting then from the pure aldehyde prepared according to the literature, 14 it was reacted with acetamide under the same conditions as before, but in the exclusive presence of Co 2 (CO) 8 . In this case the isolated product was analyzed again by 1 H NMR and the same diastereomeric composition was found.…”

“…the synthesis of heterocyclic compounds, were developed by Izawa. 7 In the past few years Beller and co-workers have described the palladium-catalyzed amidocarbonylation of aldehydes, 8 providing significant advantages over the cobalt system. They presented not only the applicability of the palladiumcatalyzed amidocarbonylation, but also reported about newly synthesized important non-natural amino acids and the first application of acetals instead of aldehydes in this reaction.…”

Palladium‐catalyzed selective alkoxycarbonylation of N‐vinylphthalimide

“…The amidocarbonylation reaction utilizing cobalt 1 and palladium 2 catalysts is an interesting tool for the synthesis of N-acyl amino acid from carbon monoxide, amides and aldehydes, but the products obtained above are mostly racemic N-acyl-α-amino acids. Beller and Eckert 3 only obtained about 10% e.e.…”