Reactions of recoiling silicon atoms with phosphine and butadiene, and the addition of silylene to butadiene

Chemical Kinetics and Hot Atom Chemistry — Present Status and Future Perspectives

“…from the addition of thermally generated :SiH 2 to butadiene [197,199] made silylene addition a likely route to this product in the recoil system. A stepwise formation of the five-membered cyclic silylene is shown on the basis of mechanistic studies with thermally generated silylenes that revealed a nonconcerted addition to butadiene [205][206][207],…”

“…A recent example from silicon chemistry indicates that product studies can be quite revealing mechanistically for polyvalent recoil atoms, particularly if some supplementary information is available from thermally induced reaction studies. Both the TANG and GASPAR groups have studied the reactions of recoiling silicon atoms with butadiene [196][197][198][199], 31 Si + Hi 31 Si 31 SiC 4 H 6 [197,199] Possible structures for 31 [196], an apparent product of silylene addition. The major product, however, was assigned an empirical formula 31 SiC 4 H 6 and the silacyclopentadiene structure was favored [197], although attempts to synthesize the authentic compound have thus far been unsuccessful.…”

“…Both the TANG and GASPAR groups have studied the reactions of recoiling silicon atoms with butadiene [196][197][198][199], 31 Si + Hi 31 Si 31 SiC 4 H 6 [197,199] Possible structures for 31 [196], an apparent product of silylene addition. The major product, however, was assigned an empirical formula 31 SiC 4 H 6 and the silacyclopentadiene structure was favored [197], although attempts to synthesize the authentic compound have thus far been unsuccessful. Of the possible structures for 31 [193] 1970 [194] 1974 [195] 4.…”

Tetramethyl-1-silacycloprop-2-ene: its characterization and reactions

“…In 1974 Gaspar, Hwang, and Eckelman [99] reported the addition of thermally generated :SiH2 to 1,3-butadiene, while 46 However, the above reaction sequence is only speculative and is in direct contrast to Barton's findings that tetramethyldisilene rearranges to the silylsilylene. The following sequence is just as likely.…”

Gas‐Phase Synthesis of 1‐Silacyclopenta‐2,4‐diene

“…[14][15][16][17] Recent studies reported an ovel method for synthesizing siloles through a[ 2 + +2+ +1] cycloaddition. [18,19] Considering the difficulties in preparation, their sensitivity to air, short lifetimes,a nd the tendencyt of orm dimers,free siloles represent one of the least explored classes of organosilicon molecules.Despite indirect evidence for the formation of silole as at ransient intermediate through the detection of its [4+ +2] adduct and its catalytic hydrogenation [20][21][22][23] along with matrix-isolation studies, [24,25] the isolation of the parent silole (1-silacyclopenta-2,4-diene) in the gas phase has eluded synthetic chemists for the last five decades.…”