@article {2905, title = {CRYSTAL-STRUCTURE CORRELATIONS IN THE PHOTOCHEMISTRY OF DIMETHYL 9,10-DIMETHYL-9,10-DIHYDRO-9,10-ETHENOANTHRACENE-11,12-DICARBOXYLATE}, journal = {Acta Crystallographica Section B-Structural Science}, volume = {49}, year = {1993}, note = {ISI Document Delivery No.: KM629Times Cited: 15Cited Reference Count: 25Part 1}, month = {Feb}, pages = {107-116}, type = {Article}, abstract = {{The photochemistry of the title 9,10-dimethlydi-benzobarrelene-11,12-diester (1) in solution and in the solid state exhibits unique differences as a function of reaction medium. In acetone the normal di-pi-methane reaction leads to a semibull-valene derivative, dimethyl 4b,8b-dimethy-4b,8b,8c,-8d-tetrahydrodibenzo[a,f]cyclopropa[calpentalene -gc,8d-dicarboxylate (2), while in acetonitrile an additional cyclooctatetraene (COT) photoproduct, dimethyl 5,11-dimethyldibenzo[a,e]cyclooctene-6,12-dicarboxylate (3), is obtained. In the solid state a new pentalene, dimethyl 5, 10-dimethyl-5, 10-dihydro-indeno[2,1-a]indene-5,10-dicarboxylate (4), is formed as the major product. Crystal data for (1), (3) and (4): T = 294 K, Cu Kalpha}, keywords = {1, 2-MIGRATION, EXPLORATORY ORGANIC-PHOTOCHEMISTRY, PHOTOPRODUCTS, PI-METHANE REARRANGEMENT, SOLID-STATE PHOTOCHEMISTRY, SUBSTITUTED DIBENZOBARRELENE}, isbn = {0108-7681}, url = {://A1993KM62900013}, author = {Pokkuluri, P. R. and Scheffer, J. R. and Trotter, J.} } @article {2905, title = {CRYSTAL-STRUCTURE CORRELATIONS IN THE PHOTOCHEMISTRY OF DIMETHYL 9,10-DIMETHYL-9,10-DIHYDRO-9,10-ETHENOANTHRACENE-11,12-DICARBOXYLATE}, journal = {Acta Crystallographica Section B-Structural Science}, volume = {49}, year = {1993}, note = {ISI Document Delivery No.: KM629Times Cited: 15Cited Reference Count: 25Part 1}, month = {Feb}, pages = {107-116}, type = {Article}, abstract = {{The photochemistry of the title 9,10-dimethlydi-benzobarrelene-11,12-diester (1) in solution and in the solid state exhibits unique differences as a function of reaction medium. In acetone the normal di-pi-methane reaction leads to a semibull-valene derivative, dimethyl 4b,8b-dimethy-4b,8b,8c,-8d-tetrahydrodibenzo[a,f]cyclopropa[calpentalene -gc,8d-dicarboxylate (2), while in acetonitrile an additional cyclooctatetraene (COT) photoproduct, dimethyl 5,11-dimethyldibenzo[a,e]cyclooctene-6,12-dicarboxylate (3), is obtained. In the solid state a new pentalene, dimethyl 5, 10-dimethyl-5, 10-dihydro-indeno[2,1-a]indene-5,10-dicarboxylate (4), is formed as the major product. Crystal data for (1), (3) and (4): T = 294 K, Cu Kalpha}, keywords = {1, 2-MIGRATION, EXPLORATORY ORGANIC-PHOTOCHEMISTRY, PHOTOPRODUCTS, PI-METHANE REARRANGEMENT, SOLID-STATE PHOTOCHEMISTRY, SUBSTITUTED DIBENZOBARRELENE}, isbn = {0108-7681}, url = {://A1993KM62900013}, author = {Pokkuluri, P. R. and Scheffer, J. R. and Trotter, J.} } @article {7346, title = {SELECTIVE SOLID-STATE PHOTOREARRANGEMENT THROUGH THE LESS STABLE OF 2 POSSIBLE BIRADICAL INTERMEDIATES}, journal = {Journal of Organic Chemistry}, volume = {57}, number = {5}, year = {1992}, note = {ISI Document Delivery No.: HG741Times Cited: 12Cited Reference Count: 32}, month = {Feb}, pages = {1486-1494}, type = {Article}, abstract = {The photochemistry of methyl 2-benzoyl-1,4-dihydro-1,4-ethenonaphthalene-3-carboxylate is completely medium-dependent. In solution, two primary di-pi-methane-type photoproducts are formed. Neither of these products is produced when the photolysis is carried out in the solid state; instead, three new photoproducts are formed. The results are interpreted as being due to reaction through 1,3-biradical intermediates, the more stable of which are preferred in solution whereas the less stable ones are formed in the solid state as a result of topochemical restrictions of molecular motion. X-ray crystallographic evidence in support of these ideas is presented and discussed.}, keywords = {CRYSTALS, EXPLORATORY ORGANIC-PHOTOCHEMISTRY, HYDROGEN ABSTRACTION REACTIONS, POLAR SUBSTITUENTS, REARRANGEMENT}, isbn = {0022-3263}, url = {://A1992HG74100030}, author = {Pokkuluri, P. R. and Scheffer, J. R. and Trotter, J. and Yap, M.} } @article {7346, title = {SELECTIVE SOLID-STATE PHOTOREARRANGEMENT THROUGH THE LESS STABLE OF 2 POSSIBLE BIRADICAL INTERMEDIATES}, journal = {Journal of Organic Chemistry}, volume = {57}, number = {5}, year = {1992}, note = {ISI Document Delivery No.: HG741Times Cited: 12Cited Reference Count: 32}, month = {Feb}, pages = {1486-1494}, type = {Article}, abstract = {The photochemistry of methyl 2-benzoyl-1,4-dihydro-1,4-ethenonaphthalene-3-carboxylate is completely medium-dependent. In solution, two primary di-pi-methane-type photoproducts are formed. Neither of these products is produced when the photolysis is carried out in the solid state; instead, three new photoproducts are formed. The results are interpreted as being due to reaction through 1,3-biradical intermediates, the more stable of which are preferred in solution whereas the less stable ones are formed in the solid state as a result of topochemical restrictions of molecular motion. X-ray crystallographic evidence in support of these ideas is presented and discussed.}, keywords = {CRYSTALS, EXPLORATORY ORGANIC-PHOTOCHEMISTRY, HYDROGEN ABSTRACTION REACTIONS, POLAR SUBSTITUENTS, REARRANGEMENT}, isbn = {0022-3263}, url = {://A1992HG74100030}, author = {Pokkuluri, P. R. and Scheffer, J. R. and Trotter, J. and Yap, M.} }