Photoreaction of 9-dicyanomethylene-1,2,3,4-tetrahydro-1,4-methanonaphthalene: the 1,3-carbon migrations and the ethylene extrusion to dicyanoisobenzofulvene

Irradiation of 9-dicyanomethylene-1,2,3,4-tetrahydro-1,4-methanonaphthalene gave 3,3-dicyano-1,2,3,8b-tetrahydrocyclopent [a] indene and 2-dicyanomethylene-2H-indene.     

HIGH-FREQUENCY VIBRATIONS OF CORRUGATED CYLINDRICAL PIEZOELECTRIC SHELLS

Coupled extensional and flexural cylindrical vibrations of a corrugated cylindrical piezoelectric shell consisting of multiple pieces of circular cylindrical surfaces smoothly connected along their generatrix are studied. To validate the results for the case of relatively thick shells or equivalently high-frequency modes with short wavelengths, existing analysis is extended by considering shear deformation and rotatory inertia. An analytical solution is obtained. Based on the solution, resonant frequencies and mode shapes are calculated.     

D3-trishomocubanetrione synthesis and optical resolution

A large-scale synthesis for the title compound rac-1 based on 11-oxahexacyclo-[5.4.1.0^2,6.0^3,10.0^4,8.0^9,12] dodecan-5-one (12) as the key intermediate and an efficient procedure for the optical resolution of rac-1 via the diastereomeric ketals with (R,R)-2,3-butandiol are reported. The absolute configuration is established by correlating the optically pure (+)-trione ([α]_D +949°) with (-)-trishomocubane.     

Total synthesis of 1-thio-α-tocopherol: A sulfur-containing analogue of vitamin E.

The title compound, has been synthesized in ten steps in an overall yield of 2%.     

Stereoselective total synthesis of the cembranolide diterpene anisomelic acid

A highly stereoselective total synthesis of the cembranolide diterpene anisomelic acid has been achieved via a convergent route. Macrocyclization was effected by a (Z)-selective intramolecular Horner-Emmons condensation.     

A highly convergent preparation of phosphonyloxyacylamino acids:

A very simple, mild and efficient method for the preparation of phosphonyloxyacylamino acids from readily available starting materials is described.