Stereochemical Studies on Protonated Bridgehead Amines. 1H NMR Determination of Cis and Trans B-C Ring-Fused Structures for Salts of Hexahydropyrroloisoquinolines and Related C Ring Homologues. Capture of Unstable Ring-Fused Structures in the Solid

Article abstract of DOI:10.1021/ja00189a020

Acid-addition salts of tricyclic isoquinolines 2a/b, 3a/b ,4a-4c, 5, 6a/b, 7, 8a/b, 9a/b, and 17a/b were studied by high-field 1H NMR in CDCl3 solution.Cis (e.g., 14 and 15 in Figure 1) and trans (e.g., 13) B-C ring-fused structures were identified by usi