142295-03-2Relevant academic research and scientific papers
Contributions to the Chemistry of Boron, 212. - Azaphosphoniaborataborolidines and their Thermolysis to Diazaphosphadiborinanes
Ederer, Bernd,Ederle, Henry,Noeth, Heinrich
, p. 2213 - 2222 (2007/10/02)
Me3SiN=PN(SiMe3)2 (1) adds Lewis-acidic diborylmethanes CH22 (6a-d, X = Cl, Me, Ph, Mes) to yield the five-membered azaphosphoniaborataborolidines 9a-d by haloboration and formation of an intramolecular coordinative phosphorus boron bond.However, the less Lewis-acidic diborylmethane CH22 does not react with 1.NMR studies on 9 exhibit conformational dependence of the ring system on the bulkiness of X, suggesting a decreasingly folded structure for X = Mes > Ph > Me and a planar ring for X = Cl, the latter proven by an X-ray structure analysis. 9a,b rearrange their ring framework on heating with elimination of Me3SiCl to give diazaphosphadiborinanes 7.Compound 7b shows the typical reactions of a diamino(chloro)phosphane: oxidation by S8 yields the corresponding phosphane sulfide 17 while AlCl3 abstracts a chloride ion with formation of a phosphenium tetrachloroaluminate 13.In the reaction of 7b with BBr3 halogene exchange (to 16) dominates, while a phosphane borane adducts (15) is formed in a side reaction only. Key Words: Diborylmethanes / Amino-imino-phosphane / Haloboration / Phosphane borane adducts, intramolecular / Phosphenium ion, cyclic
