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A reaction of 2,2,2-trihalobenzo-1,3,2-dioxaphospholes with terminal alkylacetylenes proceeds under mild conditions (∼20 °C) and leads to the formation of 4-alkylbenzo[ e]-1,2-oxaphosphinine 2-oxide derivatives. The presence of aliphatic substituents in acetylene decreases (as compared to their aromatic counterparts described earlier) regioselectivity of halogenation of benzo fragment in 4-alkylbenzo[ e]-1,2-oxaphosphinines: besides predominant 4-alkyl-2,6-dihalobenzo[ e]-1,2-oxaphosphinines, minor 2,7- and 2,8-dihalo-substituted 4-alkylbenzo[ e]-1,2-oxaphosphinines are formed. An unusual thermal isomerization of 4-alkyl-2-fluorobenzo[ e]-1,2-oxaphosphinines to 4-alkylidene-2-fluoro-3,4-dihydrobenzo[ e]-1,2-oxaphosphinines was discovered. Molecular and supramolecular structures of some 4-alkylbenzo[ e]-1,2-oxaphosphinines were studied by X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

The 4-aryl(alkyl)benzo[e]-1,2-oxaphosphorine derivatives (phosphacoumarins) were obtained by the reaction of 2,2,2-trihalogenobenzo[d]-1,3,2-dioxaphospholes with terminal acetylenes. The reactions of phosphacoumarins with halogens and Grignard reagents were investigated. [ABSTRACT FROM AUTHOR]

NMR and IR spectroscopy and X-ray diffraction were used to show that the reaction of 2,2,2-trichloro- and 2,2,2-tribromo-5-methylbenzo[d][1,3,2]dioxaphospholes withpara-substituted arylacetylenes proceeds with regioselective formation of 4-aryl-2-halo-7-methyl-2-oxobenzo[e][1,2]oxaphosphorines. With the trichlorophosphole, selective chlorination of the phenylene fragment in theparaposition to the endocyclic oxygen atom occurs. With the tribromophosphole, 6-bromo- and unsubstituted benzo[e][1,2]oxaphosphorines are formed as major products. The molecular and supramolecular structure of some of the obtained oxaphosphorines was studied by X-ray diffraction. [ABSTRACT FROM AUTHOR]

The article reports on the finding that 4,6-di-tert-butyl-2,2,2-trichloro-1,3,2λ5-benzodioxaphosphole, which has bulky tert-butyl groups, can react with 1-hexyne under mild conditions. This reaction produces exclusively 1,2λ5-benzoxaphosphinine derivatives. The product was confirmed by 31P nuclear magnetic resonance spectroscopy.

The article presents a study about the product in the chemical reaction of 2,2,2-trichloro-1,3,2λ5-benzodioxaphosphole-5-carbonyl chloride with hex-1-yne. The reactions of aryl- and alkylacetylenes with 2,2,2-trichloro(bromo)-1,3,2λ5-benzodioxaphosphole and some of its derivatives underlie a synthetic approach to 4-butyl-2,5-dichloro-2-oxo-1,2λ5-benzoxaphosphinine-6-carbonyl chloride.

The article investigates the reaction of dioxaphosphol with unsubstituted alkylacetylene. The reaction with propargyl chloride with phosphol resulted in two phosphorus-containing substances which gave rise to characteristic doublet signals of benzophosphorinines which were converted by hydrolysis into the corresponding acids.