Synthesis of 2,6-diaminopyridine substituted α-oxoketene S,N-acetals: Crystal structure and hydrogen bonding interactions

Abstract

Polyaza α-oxoketene S,N-acetals can exist as either enamino or imino tautomeric forms. Based on the spectroscopic data and structural analysis of one of the S,N-acetals, the stereochemistry was unambiguously assigned as an all-E-configuration. The crystal structure confirms the enamino structure and shows extensive use of C-Hâ̄X (X = N, O, and S) weak hydrogen bonding interactions, thereby generating a 3-dimensional network in solid state. [Figure not available: see fulltext.] © 2013 Indian Academy of Sciences.