Compounds with P—O—B Linkages

The existence of boraphosphates has now been well established and there appear to be at least three types of crystalline structure based on  

Recent studies of alkali borophosphates and other borophosphate minerals, have shown that BO4 and PO4 tetrahedral nnits link together by sharing their O atoms in common, to form various patterns of chains, 2-D and 3-D structures [46]. 

Hydrothermal synthesis with a mixture of ZnO, B2O3, H3PO4 and diethylene triamine, yields a crystalline complex with formula (C4N3Hi6)[Zn3B3P6024i. This contains helices of comer-sharing 

BO4 and PO4 tetrahedra which are interconnected with Zn04 tetrahedra to form a three-dimensional structure [56], 

A few organophosphorus boron compounds with P-O-B linkages are also known. Tris(diethylphosphite)borane, for example, can be obtained by reaction (9.122), but it is reported to re-arrange as indicated [35], The product of reaction (9.123) is unstable and the P-O-B bond is replaced by P-B on heating. 

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