title: Rigid core vinamidinium salts and their N,N'-rotamers.
abstract: The power of proton magnetic resonance spectroscopy to unravel stereochemical details is amply demonstrated. O-Methylation of 3-methylamino-5,5-dimethyl-2-cylohexen-1-one (1a) produces stable diastereomers, (Z)- and (E)-N-(3-methoxy-5,5-dimethyl-2-cyclohexen-1-ylidine)-N-methylaminium iodide (2a). As predicted by computation and confirmed by spectroscopy, the (Z)-vinylogous imidate salt predominates. Reaction of 2a with primary and secondary amines furnished a number of vinamidinium salts, including N-(3-methylamino-5,5-dimethyl-2-cyclohexen-1-ylidene)-N-methylaminium iodide (3a). Two rotamers of 3a were identified and characterized. A substantial number of additional compounds 2 and 3 are included in the study.
authors.affiliation: Department of Chemistry, Concordia College, Moorhead, MN 56562, USA. ostercam@cord.edu
authors.forename: Daryl L
authors.initials: DL
authors.lastname: Ostercamp
authors.forename: Yen
authors.initials: Y
authors.lastname: Dinh
authors.forename: David
authors.initials: D
authors.lastname: Graff
authors.forename: Sarah
authors.initials: S
authors.lastname: Wiles