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Three simple methods for the synthesis of geminal triazides are described: Starting from 1) 3-oxocarboxylic acids, 2) iodomethyl ketones, or 3) terminal olefins, a range of triazidomethyl ketones can be constructed under mild oxidative reaction conditions by the use of IBX-SO3 K, a sulfonylated derivative of 2-iodoxybenzoic acid (IBX), and NaN3 as an azide source. This is the first report of representatives of this novel class of triazide compounds: Despite their high nitrogen content, the geminal triazides are easy to handle, even when preparative-scale syntheses are performed. (Caution: These procedures still require protective measures!) The triazides are now broadly available for further studies regarding their properties and reactivity. Furthermore, we show how the method can be used to provide α-azidoesters, which are potential building blocks for amino acids., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Trichloroacetimidate derivatives of prochiral (Z)-2-alken-1-ols react at room temperature with carboxylic acids to give chiral 3-acyloxy-1-alkenes in high enantiopurity in the presence of di-mu-acetatobis[(eta5-(S)-(pR)-2-(2'-(4'-methylethyl)oxazolinyl)cyclopentadienyl,1-C,3'-N)(eta4-tetraphenylcyclobutadiene)cobalt]dipalladium (COP-OAc) or its enantiomer. This reaction has broad scope, proceeds with predictable high stereoinduction, is accomplished at room temperature using high substrate concentrations and low catalyst loadings, and likely proceeds by a novel mechanism.