• Journal of Photoscience
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• 제9권1호
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• pp.1-4
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• 2002

This brief review deals with the thermal or photochemical synthesis and reactions of silacyclopropene or 1-sila-1,2-propadiene. The novel intramolecular reactions of silacyclopropene or 1-sila-1,2-propadiene are also discussed.

• Bulletin of the Korean Chemical Society
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• 제22권11호
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• pp.1202-1206
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• 2001

Irradiation of 1-(o-hydroxyphenyl)-2-pentamethyldisilanylethyne 1 in a concentrated benzene solution has provided photodimer product 7 along with other reported photoproducts. Irradiation of 1 in methanol yields 1-(o-hydroxyphenyl)-2-trimethylsilylethyne 2 and its reduction product 13, via silacyclopropene intermediate 10, and the reduction product 8 and two methanol addition products, 11 and 12, via o-hydroxyphenylethyne. Photolysis of 1 with acetone in deaerated methylene chloride affords site specific and regioselective 1 : 1 adduct 16 via silacyclopropene intermediate 10.

• 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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• 제1권2호
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• pp.119-122
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• 1994

$PdCI_2(PPh_3)_2$-catalyzed photolysis of 1-phenyl-4-(pentamethyldisilanyl)buta-1,3-diyne (1) in dry benzene gives 1,4-disilacyclohexa-2,5-diene type dimerization products(3-6) via silacyclopropene. The silacyclopropene is formed from the singlet excited state of 1 and this silacyclopropene reacts with $(PPh_3)_2Pd^0$to form palladasilacyclobutene. In this reaction, the silylene-palladium complex is generated and reacts with 1 to give another silacyclopropene. $PdCI_2(PPh_3)_2$catalyzed photolysis of 1 with other alkynes supports the involvement of this silylene complex.

• Bulletin of the Korean Chemical Society
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• 제19권6호
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• pp.686-689
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• 1998

Irradiation of 1-(o-allyloxyphenyl)-2-pentamethyldisilanylethyne (2) in methanol yields two 1 : 1 photoaddition products (3 and 4) via silacyclopropene intermediate. Photolysis of (2) with acetone in deaerated methylene chloride yields site specific and regioselective 1: 1 adducts (7 and 8) via silacyclopropene and 1-sila-1,2-propadiene intermediate, respectively.

• Bulletin of the Korean Chemical Society
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• 제16권10호
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• pp.988-990
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• 1995

No fluorescence was observed from 1-aryl-4-(pentamethyldisilanyl)buta-1,3-diynes except 1-(1-naphthyl)-4-(pentamethyldisilanyl)buta-1,3-diyne. Irradiation of 1-aryl-4-(pentamethyldisilanyl)buta-1,3-diynes (1) with methanol gives photoaddition products in relatively low yields compared to arylethynyldisilanes which show dual fluorescence. Irradiation of 1 with acetone yields site specific and regioselective 1:1 photoadducts through silacyclopropene intermediates. The triplet excited state of the silacyclopropene reacts with acetone to give addition photoproducts and the triplet energy of the silacyclopropenes lies around 260-286 kJ/mol.

• Bulletin of the Korean Chemical Society
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• 제20권5호
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• pp.547-550
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• 1999

Irradiation of 1-(o-acetoxyphenyl)-2-pentamethyldisilanyl ethyne 2 in benzene yields the photo-Fries rearrangement products 5 and 6 and a photoproduct 4 via silacyclopropene intermediate.

• 대한화학회지
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• 제37권8호
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• pp.757-764
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• 1993

Phenylsilylene(PhHSi:)의 광분해 전구체인, 1,1,1,3,3,3-hexamethyl-2-phenyltrisilane(2)과 2,3-dicarbomethoxy-1,4,5,6,7-pentaphenyl-7-silanorbornadiene(5)을 10%와 73%의 수율로 각각 합성하였다. 전구체 2를 254 nm의 빛을 조사시켜 광분해 실험시킨 결과 triethylsilane 존재하에서는 phenylsilylene이 Si-H 결합에 삽입된 생성물인 1,1,1-triethyl-2-phenyldisilane (6)이 44%의 수율로 얻어졌고, diphenylacetylene 존재하에서는 phenylsilylene이 삼중결합에 첨가된 후 diphenylacetylene과 [2＋2] 첨가반응이 일어나 얻어진 생성물, 1-phenyl-1-silacyclopenta-2,4-diene(4)과 phenyl-silylene이 삼중결합에 첨가된 다음 곧 이합체화되어진 화합물인 1,2-diphenyl-1,2-disilacyclohexa-2,5-diene(10)이 각각 68% 와 26%의 수율로 얻어졌다. Neat 광반응에서는 생성된 phenylsilylene이 분자간 C-H 삽입반응을 하여 생성된 화합물, 1,5-dihydrosilanthren(11)과 전구체 2가 Si-H 결합에 삽입된 화합물, 1,2-diphenyltrisilane(12)이 5%와 7%의 수율로 각각 얻어졌다. 같은 조건에서 화합물 5를 triethylsilane과 methanol 존재하에서 광분해시킨 결과 phenylsilylene은 생성되지 않고 분자내 1,5-sigmatropic 자리옮김에 의한 silylenolether가 생성됨을 확인하였다.