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Reactions of 5- tert-butyl-2,2,2-trichloro-, 2,2,2-tribromo-5- tert-butyl-, and 2,2-dibromo-5- tert-butyl-2-fluoro-1,3,2λ-benzodioxaphospholes with aryl- and alkylacetylenes lead to quantitative formation of 2-halo-1,2λ-benzoxaphosphinine 2-oxides which may be regarded as phosphorus analogs of natural heterocyclic compounds, coumarin and chromene. The major products (>70%) are 4-aryl-7- tert-butyl-2,6-dichloro-, 4-aryl-2-bromo-7- tert-butyl-, and 4-aryl-7- tert-butyl-2-fluoro-1,2λ-benzoxaphosphinine 2-oxides. Hydrolysis of these compounds and their treatment with amines gives the corresponding 2-hydroxy and 2-amino derivatives, as well as ammonium salts. The structure of some compounds was proved by X-ray analysis. [ABSTRACT FROM AUTHOR]

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]

It was shown for the first time that 3-chloro-, 3-bromo-, and 3-iodopropynes can react with 2,2,2-trichloro-, 2,2,2-trichloro-5-methyl-, and 5,6-dibromo-2,2,2-trichloro-1,3,2λ5-benzodioxaphospholes to give derivatives of 4-(halomethyl)-2-chloro-2 H-1,2λ5-benzoxaphosphinin-2-ones. The reaction involves nonselective chlorination of the phenylene substituent in different positions, and the resulting isomer ratio is temperature-dependent. In the reactions of 3-bromo-and 3-iodopropynes with 2,2,2-trichloro-1,3,2λ5-benzo-dioxaphosphole, a side process takes place, viz. nucleophilic substitution of bromine and iodine with chlorine. The structure of some of the prepared 4-(chloromethyl)-1,2-benzoxaphosphinines was studied by means of X-ray diffraction. [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 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.