Starting from tetrakis(trimethylsilyl)cyclobutadiene and an amidinate-supported silylene of the Roesky-type, a sequence of addition and reduction cleanly gives the elusive silapyramidane via an isolable cyclobutene intermediate with an exocyclic SiC bond. The silapyramidane features an unusually shielded 29Si NMR resonance at −448.3 ppm for the apex silicon atom. Treatment with Fe2(CO)9 results in the formation of the corresponding silapyramidane–iron complex. Silapyramidane also reacts with the cyclobutadiene starting material to cleanly afford a fluorescent spirobis(silole).

Trialkylsilyllithium species have turned out to be facilely generated by treating hexaalkyldisilanes with methyllithium in the presence of tris(N,N-tetramethylene)phosphoric triamide (TPPA) as an activator, which can be trapped by boron electrophiles to afford silylboronic esters including long-awaited Me3Si–B(pin).

No abstract

Trialkylsilyl lithium species have turned out to be facilely generated by treating hexaalkyl disilanes with methyl lithium in the presence of tris(<i>N,N</i>-tetramethylene)phosphoric triamide (TPPA) as an activator, which can be trapped by boron electrophiles to afford silylboronic esters including long-awaited Me₃Si–B(pin).