title: (+)-2-(1,2,3,4,4a,5,6,7-Octahydro-4a,8-dimethyl-7-oxo-2-naphthyl)propionic acid: catemeric hydrogen bonding in a bicyclic sesquiterpenoid keto acid.
abstract: The title compound, C(15)H(22)O(3), derived from a naturally occurring sesquiterpenoid, has two molecules in the asymmetric unit, differing principally in the rotational conformation of the carboxyl group. Each species aggregates separately as a carboxyl-to-ketone hydrogen-bonding catemer [O.O = 2.752 (4) and 2.682 (4) A, and O-H.O = 161 (4) and 168 (4) degrees ], producing two crystallographically independent single-strand hydrogen-bonding helices, with opposite end-to-end orientations, passing through the cell in the b direction. Three intermolecular C-H.O=C close contacts exist for the ketone.
authors: Carl A. Olson Memorial Laboratories, Department of Chemistry, Rutgers University, Newark, NJ 07102, USA.
authors: Andrew P J
authors: AP
authors: Brunskill
authors: Hugh W
authors: HW
authors: Thompson
authors: Roger A
authors: RA
authors: Lalancette