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[alpha]-Amino acids and [alpha]-amino methyl esters are easily converted to their N-monoalkyl derivatives by a reductive condensation reaction using several carbonyl compounds in the presence of sodium borohydride. This reducing agent has shown a wide versatility with minor but essential procedural variations. The reaction allows the [alpha]-monodeuterium labeling of the new N-substituent by use of sodium borodeuteride. Key words: [alpha]-amino acid, [alpha]-amino methyl esters, sodium borohydride, reductive N-monoalkylation, carbonyl compounds.

In this paper we describe the unprecedented reaction between α-diazo esters 1 and iodine. The reaction, carried out in the presence of aqueous NaHCO3, afforded the Z-isomer of the corresponding unsaturated-2-iodo ester 8. The configuration of compounds 8 was determined using the 3JC&bond;H coupling between carbonyl carbon atom and alkene proton. Mechanistic considerations accounting for the observed phenomena and including quantum chemical calculations are proposed. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]