204649-38-7

Upstream product

• 563-79-1 2,3-Dimethyl-2-butene 
• 37441-95-5 1-(2-thioxobenzo[d]oxazol-3(2H)-yl)ethanone 
• 108-24-7 acetic anhydride 
• 312313-52-3 o-Hydroxy-N-(3,3,4,4-tetramethylthietan-2-ylidene)aniline 
• 19650-83-0 N-(iso-butyryl)benzoxazoline-2-thione 
• 312313-49-8 o-(2-Phenylpropanoyl)-N-(3,3,4,4-tetramethylthietan-2-ylidene)aniline 
• 312313-34-1 3-phenyl-1-(2-thioxobenzo[d]oxazol-3(2H)-yl)propan-1-one 
• 204649-41-2 o-(2-Methylpropanoyl)-N-(3,3,4,4-tetramethylthietan-2-ylidene)aniline 
• 230958-81-3 methyl 3',3',4',4'-tetramethylspiro[3H-benzoxazole-2,2'-thiethane]-3-carboxylate 
• 49740-24-1 methyl 2-thioxo-3H-benzoxazole-3-carboxylate 

Downstream Products

• 312313-52-3 o-Hydroxy-N-(3,3,4,4-tetramethylthietan-2-ylidene)aniline 

Relevant academic research and scientific papers

Photoaddition of N-acylbenzoxazole-2-thiones to alkenes

N-Acylbenzoxazole-2-thiones 1 undergo photoaddition with alkenes 2 in a regiospecific manner to yield benzoxazole derivatives 3-9 and/or the unexpected, iminothietanes 10-14 via spirocyclic aminothietane intermediates, depending on the nature of the substituents both on the N-atom of 1 and those present in the alkenes 2.

Photocycloaddition reactions of alkyl and aryl 2-thioxo-3H-benzoxazole-3-carboxylates to Alkenes

The photochemical reactions of alkyl and aryl 2-thioxo-3H-benzoxazole-3-carboxylates 1 have been examined. Irradiation of 1 in the presence of tetra- and trisubstituted alkenes 2a and 2b, 2-methylprop-2-ene nitrile 2e, and dienes 2f and 2g gave [2+2] cycloadducts of the C=S bond of 2-thioxobenzoxazoles and the C=C bond of alkenes, spiro[benzoxazole-thietanes] 3, 4, 8-13, 15, 18, 20, 23-26 in moderate- to-good yields. The photoaddition reactions proceed in a regiospecific manner. The spirocyclic compounds obtained are indefinitely stable at room temperature. Irradiation of 1a in the presence of 1,1- and 1,2-disubstituted alkenes 2c and 2d yielded the products 5-7 of oxazole-ring cleavage. Compound Id also underwent photoaddition with alkenes to yield spiro[benzoxazole-thietanes] and/or 2-substituted benzoxazoles and/or iminothietanes, depending on the nature of the substituents present in the alkenes. On intramolecular [2 + 2] photoadduct, tetracyclic 27, was obtained, when ethenyl 2-thioxobenzoxazole-3-carboxylate 1e was irradiated.

Photochemical reactions of N-acylbenzoxazole-2-thiones

The photochemical reactions of N-acylbenzoxazole-Z-thiones 1 are examined. Irradiation of N-acylbenzoxazole-2-thiones 1 in the presence of a variety of alkenes 2 yields 2-substituted benzoxazoles 3-20 and/or the unexpected products, iminothietanes 21-29 by intramolecular trapping of the acyl group by thiolate anion of the zwitterionic intermediate I and by the phenolate anion of the zwitterionic intermediate II, respectively, derived from the spirocyclic aminothietanes AT which are formed by regioselective [2+2] cycloaddition of the carbon-sulfur double bond of 1 to the alkene double bond. The Royal Society of Chemistry 2000.