134262-00-3

Upstream product

• 134354-81-7 2,4-Di-tert-butyl-2,4-bis-(2,4,6-trimethyl-phenyl)-[1,3,2,4]diphosphadisiletane 
• 134451-47-1 {(2,4,6-trimethylphenyl)CMe₃SiPLi}2 

Relevant academic research and scientific papers

A FACILE ROUTE TO A NEW CLASS OF SILICON- AND GERMANIUM-PHOSPHORUS COMPOUNDS: P2Si2- AND Ge2P2-BICYCLOBUTANES - SYNTHESIS AND INVERSION

A new synthesis of 1,3-diphospha-2,4-disilabicyclobutanes and of the novel 1,3-digerma-2,4-diphosphabicyclobutane derivative as well as their exo,endo -> exo,exo-isomerization are discussed.

A Facile Synthesis of 1,3-Diphospha-2,4-disilabicyclobutanes and Isomerization by Silicon Inversion

Dilithiation of the PH positions of the P2Si2 cyclobutanes 2a-h with n-BuLi and treatment with tBuHgCl leads to the 1,3-bis(tert-butylmercurio) compounds 3a-h.According to NMR spectroscopy and X-ray structural analysis the tert-butylmercurio groups at phosphorus occupy trans configuration.Photolysis of solutions of 3a-d and 3f, g in toluene yields the corresponding 1,3-diphospha-2,4-disilabicyclobutanes 1a-d and 1f, g.Interestingly, the dimercury compound 3e (R = mesityl and tert-butoxy) is quite stable in visible light, probably due to intramolecular donor (tBuO) acceptor (Hg) stabilization.Starting from 3b, the light-induced elimination of the tBuHg groups gives the expected exo,endo-P2Si2-bicyclobutane 1b only as intermediate.The final product of the latter photolysis is the CMe3/CMe3-exo,exo isomer 1b'.The formation of 1b' from 1b is an irreversible silicon inversion process caused by unfavourable interaction in the endo substituents in 1b.In comparison, the exo,endo isomer of 1g (R = isityl and CMe3 at silicon) does not rearrange to the Me3C/Me3C-exo,exo derivative 1g' under similar photolysis conditions or when heated at 140 deg C for several days.The route to 1,3-diphospha-2,4-disilabicyclobutanes 1 described herein allows the synthesis of new derivatives which cannot be prepared from disilenes and white phosphors. Key words: 1,3,2,4-Diphosphadisiletanes, 1,3-bis(tert-butylmercurio)-substituted, Mercury-phosphorus bond, 1,3-Diphospha-2,4-disilabicyclobutanes, Silicon inversion.