Heterocycles containing Phosphorus with or without Oxygen

11 Heterocycles containing Phosphorus (with or without Oxygen) 

The synthesis and some reactions of the aldehyde (371) from the alkene (370) have been described, e.g. oxidation to the carboxylic acid, reduction to the 4-methyl compound, and Grignard and Wittig reactions. When the dioxaphos-phorinan (372), in which all methyl groups are equatorial, was oxidized with peroxide, a mixture of the stereoisomers (373) was obtained. 

2-dioxaphosphorin (375) is obtained from the reaction of the diene-diol form of pentane-2,4 -dione with complexes of phenylphosphonous dichloride with chromium carbonyl (374).  

The stereochemistry of the thiono-thiolo rearrangement of derivatives of 2-thiono-l,3,2-dioxaphosphorinan (376) in trifluoroacetic acid proceeds with inversion of configuration. The reaction was also investigated in other media. From an n.m.r. study of 2,4,5,6-tetraphenyl-l,3,5-dioxaphosphorinan (377), its F-oxide, and its P-sulphide, all the phenyl groups appear to be in the equatorial positions.The mechanism of the reaction of phosphorus anilides (378) with carbonyl compounds to give (a-anilinoalkyl)phosphonates (379) has been studied in the presence and absence of an amine hydrochloride. 

Vinyl acetate reacted with PCI5 at about -30 °C treatment of the resultant compound with ethylene oxide gave the 2,4-dioxaphosphacyclohexane (2,4-dioxaphosphorinan) (380) in 18.9% yield. 

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