Photodimerization crystals

Enkehnann V, Wegner G (1993) Single-crystal-to-single-crystal photodimerization of cinnamic acid. J Am Chem Soc 115 10390-10391... 

Tanaka K, Toda F, Mochizuki E, Yasui N, Kai Y, Miyahara I, Hirotsu K (1999) Enantiose-lective single-crystal-to-single-crystal photodimerization of coumarin and thiocoumarin in inclusion compounds with chiral host compounds. Angew Chem Int Ed Engl 38 3523-3525... 

An interesting example of crystal engineering and topochemical reactivity is provided by 2-benzyl-5-benzylidene-cyclopentanone(BBCP) derivatives which undergo single crystal-single crystal photodimerization (Jones et al, 1980). In the monomer... 

Diffusion control and pre-association in nitrosation, nitration, and halogenation, 16, 1 Dimethyl sulphoxide, physical organic chemistry of reactions, in, 14, 133 Diolefin crystals, photodimerization and photopolymerization of, 30, 117 Dipolar aptotic and protic solvents, rates of bimolecular substitution reactions in,... 

Single-Crystal to Single-Crystal Photodimerization of Coumarin and Thiocoumarin... 

The preparation and properties of the charge transfer salt between azonia derivative (2 and 246) and tetracyanoquinodimethane (TCNQ) were reported (88MI2). Wang and Jones reported that acridizinium salt underwent single crystal — single crystal photodimerization (87T1273). 

Honda, K., Nakanishi, F. and Feeder, N. (1999) Kinetic and mechanistic study on single-crystal-to- single-crystal photodimerization of 2-benzyl-5-benzylidenecyclopentanone utilizing X-ray diffraction./. Am. Chem. Soc., 121, 8246-8250. 

Under rare circumstances it may happen that the molecular shape of two monomers and the dimer, and their crystal parameters, are so nearly identical that a topotactic phototransformation occurs single crystal into single crystal. This is realized in intramolecular cases like [2,2]-(9,10)-an-thracenophane 17 and its [4 + 4]-photoisomer 18 [31]. However, it was also possible to find some rare intermolecular cases of topotactic single crystal into single crystal photodimerizations with chalcones like 2-ben-zyl-5-benzylidene-cyclopentanone 19 [32]. Since there is virtually no mol-... 

Hosomi, H., Ito, Y, and Ohba, S., Crystal-to-crystal photodimerization of tra s-cinnamamides, Ohba, S., Hosomi, H., and Ito, Y, In situ x-ray observation of pedal-hke conformational change and dimerization of trans-cinnamamide in cocrystals with phthaKc acid, /. Am. Chem. Soc., 123, 6349, 2001. 

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