X-ray investigations of bicyclic alpha-methylene-delta-valerolactones. III. trans-(4aR,8aR)-4a-Methoxy-3-methyleneperhydrochromen-2-one.

The title compound, C11H16O3, adopts a conformation in which the delta-valerolactone and cyclohexane rings are almost coplanar with one another. The beta-methoxy substituent occupies an axial position with respect to the cyclohexane ring. The delta-valerolactone moiety adopts a half-chair arrangement, while the cyclohexane ring exists in a chair conformation.

X-ray investigations of bicyclic alpha-methylene-delta-valerolactones. II. (4aS,8aS)-4a-methyl-3-methyleneperhydrochromen-2-one.

The title compound, C(11)H(16)O(2), adopts a semifolded conformation with the delta-lactone and cyclohexane rings almost perpendicular to one another. The beta-methyl substituent occupies an axial position with respect to the cyclohexane ring. The delta-lactone moiety adopts a slightly distorted half-chair arrangement, while the cyclohexane ring exists in an almost ideal chair conformation.