• Bulletin of the Korean Chemical Society
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• 제7권3호
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• pp.228-230
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• 1986

Diacetylene compound, 1,4-diphenyl-1,3-butadiyne, was photolyzed with 5-fluorouracil as a model reaction of the phototoxic conjugated poly-ynes with DNA or RNA and obtained a [2 + 2] photocycloadduct. The structure of the photoadduct was determined by spectral methods and compared with the [2 + 2] photoadducts of 1,4-diphenyl-1,3-butadiyne with tetramethylethylene and dimethyl fumarate.

• Journal of Photoscience
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• 제6권1호
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• pp.7-12
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• 1999

Irradiation of 1 , 4-diphenylbut-1-en-3-yne 1 and some p-quinones in dichloromethane with 300nm UV light yield tow types of adducts, i.e., p-quinomethanes and cyclobutanes, in which the former were produced via the rearrangement of the intially formed spiro-oxetene intermediates. On the other hadn 1 added to o-quinones to give three types of adducts, i.e., 1, 3-dienes, 1, 4-dioxenes, or spiro-oxetanes, in which the former were found to be applied to synthesize phenanthrene derivatives. A methoxy derivative of enyne 39 was synthesized to investigate the type of thephotoaddition to o-quinones, in which 1, 4-dioxenes were obatained.

• Journal of Photoscience
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• 제6권1호
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• pp.13-19
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• 1999

Irradiation of 1-(o-allyloxyphenyl)-2-pentamethyldisilanylenthyne 2a in methanol yields two 1 : 1 photoaddition products 3 and 4 via silacyclopropene intermediate. Photolysis of 2a with acetone in deaerated methylene chloride yields site specific and regioselective 1 : 1 adducts 6 ad 7 via silacyclopropene and 1-sila-1, 2-propdiene intermediate, respectively. Photolysis of 2a and 1-(o-(3', 3'-dimethyl-2'-propenylox)phenyl)-2-pen-tamethyldisilanylethyone 2b in benzene provides novel stereoselevtive intramolecular cyclization products 10 and 11, respectively. Irradiation of 1-(o-acetoxyphenyl)-2-pentamethyldisilanyl ethyne 2c in benzene yields the photo-Fries rearrangement products 18 and 19 and a photoproduct 17 via silacyclopropene intermediate. Photolysis of 1-(o-methoxycarbonlymethoxyphenyl)-2-pentamethyl disilanylenthyne 2d in benzene provides a novel intramolecular cycloaddition product 25 and 1-(o-methoxycarbonylemthoxiyphenyl)-2-trimethylsilylethyne 26 via silacyclopropene intermediate.

• Journal of Photoscience
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• 제5권4호
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• pp.143-148
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• 1998

Photoaddition reactions of ο-benzoquinones to some organic molecules were ivestigated to yield three types of photoadducts. Irradiation (350nm UV light) of a dichloromethane solution of tetrahal-1, 2- benzoquinones and 1, 4-diphenylbutadiene yielded 1, 3-dienes, which was found to be used to synthesize 1-phenylphenanthrenes. The 1, 3-dienes were also produced, when irradiated tetrahalo--1, 2-benzoquinones and 1,4-dipenylbut-1-en-3-yne in the similar conditions, which was applied to get 9-phenylphenanthrenes. An enolic compound come from the tautomerization of dibenzoylmethane was found to add to ο-benzoquinones to give, 1, 4-dioxenes and 1, 5-diketones as the major products. Although depenylbutadiyne did not add to ο-benzoquinones, diphenylacetylene added to ο-benzoquinones to give $\rho$-quinomethanes as well as two isomeric $\rho$-quinomethanes. One-way photoisomerism was observed for two isomeric $\rho$-quinomethanes.

• Bulletin of the Korean Chemical Society
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• 제10권1호
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• pp.57-60
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• 1989

UV irradiation of anthraquinone and diphenylacetylene in benzene gave 1:1 photoadduct (7) and cyclization product (8). The photoreaction of anthrone and diphenylacetylene in dichloromethane afforded the photooxidation products (7, 8, and 9) in air. The photoproduct (7) underwent the cyclization reaction during the purification by the column chromatography (silica gel). When irradiated with 350 nm UV light, the product (11) of benzil reacted with diphenylacetylene to give a photoadduct(12).

• Bulletin of the Korean Chemical Society
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• 제7권2호
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• pp.116-120
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• 1986

Irradiation of 1,4-diphenyl-1,3-butadiyne and 5,5-dimethyl-1-phenyl-1,3-hexadiyne with methanol yields 1:1 polar addition products, [E]- and [Z]-1,4-diphenyl-1-methoxy-1-buten-3-yne and [E]- and [Z]-5,5-dimethyl-1-methoxy-1-phenyl-1-hexen-3-yne, respectively. These geometrical isomers were converted into each other reaching the photostationary state on irradiation with 300 nm UV light. The photoaddition reaction of 1,4-diphenyl-1,3-butadiyne and 5,5-dimethyl-1-phenyl-1,3-hexadiyne with methanol seems to proceed from the zwitterionic lowest excited state.

• Rapid Communication in Photoscience
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• 제2권3호
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• pp.68-71
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• 2013

Acetone sensitized photoadditions of isopropanol to (5R)-5-menthyloxy-2-(5H)-furanone were investigated in two different microflow reactor systems. Setup A employed a commercially available glass reactor under a UVB-panel. Setup B utilized a FEP microcapillary wrapped tightly around a Pyrex cylinder with a single UVB fluorescent tube at its center. The reactions under flow conditions were subsequently compared to analogue reactions conducted in a batch chamber reactor. Overall, the microflow systems gave faster conversions and higher isolated yields. The flexible microcapillary setup, however, showed the best performance and promise in terms of future scale-up and reactor optimization.