Spirocyclic compounds of the siloxane series

Reaction of (t-Bu2SnO)3 with Organohalosilanes. Simple Formation of Open-Chain and Cyclic Stannasiloxanes

“…In addition, there were signals of low intensity at − 42.7, − 43.9, − 45.2, and −45.9 ppm (total integral 0.6) which are likely to represent higher siloxane oligomers. However, during the reaction the cyclic stannasiloxanes (Ph 2 SiOSn- t -Bu 2 O) 2 ( 7 ), t -Bu 2 Sn(OSiPh 2 ) 2 O ( 8 ),3r and t -Bu 2 Sn(OSiPh 2 O) 2 SiPh 2 ( 9 ) were formed as intermediates, as was evidenced by 29 Si and 119 Sn NMR studies (see Table ) of the reaction mixture after 1.5 h at 57 °C.…”

“…The chemistry of metallasiloxanes containing Si−O−M linkages (M = main-group elements as well as transition metals) has been extensively investigated over the last two decades and has been reviewed recently . In contrast, much less attention has been paid to the systematic development of the chemistry of stannasiloxanes, 1c,, although a number of such compounds has been described over the years. Even less is known on metallastannoxanes .…”

“…Even less is known on metallastannoxanes . Such compounds are of increasing interest as models for catalytically active metal oxide surfaces 5 or might serve as molecular precursors for well-defined inorganic polymers. 3r, Furthermore, stannasiloxanes are thought to be intermediates in polycondensation of silanols 2h,n,7 and, therefore, a better understanding of their chemistry is welcome.…”

“…So far, stannasiloxanes have been prepared by the reaction of organosilanols with organochlorostannanes in the presence of a base, 3f,l,n,r,s by the reaction of organosilanols with organotin oxides, 2e,h,3k,u or by lithium halide elimination from organosilanolates and organohalostannanes. 1c,2a,b,l-n,3b,c,e,h-k,m,t The formation of Si−O−Sn linkages was also achieved by making use of the high Bronsted acidity of silica surfaces, which allows the cleavage of Sn−C and Sn−H bonds. 5a,c,h,k,l …”

Cold Curing Composite Materials Based on ED-20 Epoxy Resin and Modified with Silicon–Heteroorganic Compounds

“…A considerable number of compounds with titanium siloxane bonds are now known. These are largely titanium siloxanes of cyclolinear or spirocyclic structure that do not contain organic groups at the titanium atoms [6].…”