(±)-trans-6,7-Dimeth-oxy-1-oxo-3-(2-thien-yl)isochroman-4-carboxylic acid.

ABSTRACT: The title compound, C(16)H(14)O(6)S, was synthesized by the reaction of 6,7-dimethoxy-homophthalic anhydride with thio-phene-2-carbaldehyde in the presence of 4-(dimethyl-amino)pyridine (DMAP) as a basic catalyst. The thio-phene ring of the title mol-ecule is disordered over two sites with occupancies of 0.877?(3) and 0.123?(3). The disorder corresponds to an approximate 180° rotation of the thio-phene ring with respect to the C-C bond linking it to the rest of the mol-ecule. The six-membered ring of the 3,4-dihydro-isochromanone ring system is not planar [puckering parameters Q(T) = 0.571?(2)?Å, ? = 115.2?(2)° and ? = 99.1?(2)°]. The benzene ring of the 3,4-dihydro-isochromanone ring system makes dihedral angles of 75.0?(2) and 77.2?(5)° with the disordered thio-phene rings. Inter-molecular O-H?O and C-H?O hydrogen bonds, as well as C-H?? inter-actions, lead to the observed supra-molecular structure.

SUBMITTER: Akkurt M 

PROVIDER: S-EPMC2969835 | biostudies-other | 2009

REPOSITORIES: biostudies-other