Synthesis of Regioisomeric Azidobutanediols

Abstract

Investigations to control the regioselectivity during the acetalization of pivalaldehyde (7) with butane-1,2,4-triol (4) were performed. Thermodynamic control led to the regioisomeric acetals 8 and 9 in the ratio 76:24, whereas kinetic control favored the five-membered acetal 9 (8/9 30:70). Tosylation, nucleophilic substitution with NaN₃, and subsequent methanolysis of the regioisomeric acetals 8 and 9 provided the regioisomeric 4-azidobutanediols 5 and 6, which are considered as valuable building blocks for the synthesis of novel NMDA-receptor antagonists.

Key words

acetals - azides - regioselectivity - medicinal chemistry - NMDA-antagonists

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