Pyrolysis of trichlorosilane in the presence of chloroform

Abstract

The pyrolysis of trichlorosilane in the presence of different amounts of chloroform and the copyrolysis of HSiCI 3 with buta-l,3-diene in the presence of I tool.% chloroform were studied. The enthatpies of formation of products resulting from the pyrolysis of HSiCI 3 in the presence of chloroform were calculated by the quantum chemical method. Based on the thermochemical data as well as data from GLC and mass spectrometry, it was concluded from the condensate composition that introduction of chloroform into the zone of pyrolysis of HSiCI 3 favors generation of silylenes.

Effect of chloralkanes on the phenyltrichlorosilane synthesis by gas phase condensation

“…On the one hand, the chlorine free radical facilitates the transformation of trichlorosilane to the trichlorosilyl radical (Step ⑬); on the other hand, it accelerates the transformation of the trichlorosilyl radical to tetrachlorosilane (Step ⑰), so the selectivity to phenyltrichlorosilane decreases. Steps ⑥ to ⑫ show the most probable step for dichlorosilylene generation [11]. Some other possible steps of dichlorosilylene generation are shown as Steps ⑩ and ⑪.…”

“…(6)]. Heinicke investigated the copyrolysis of trichlorosilane with chlorobenzene and 1,3-butadiene without a free radical initiator and detected no dichlorosilylene [14], while Krasnova showed that the introduction of chloroform favored the generation of silylenes [11]. Several researches used conjugated dienes to react with dichlorosilylenes [19][20][21][22].…”

“…Goetze et al reported that alkanes, diazenes and organodisilanes can be used as a free radical initiator in the synthesis of organosilanes [10]. Krasnova investigated the pyrolysis of trichlorosilane in the presence of chloroform (CHCl 3 ) and concluded that chloroform enhanced the conversion of trichlorosilane and the yield of desired products [11]. However, few researches have reported the role of chloroform and other chloralkanes in this process.…”

“…Heinicke concluded that without a free radical initiator, the trichlorosilyl radical was the main intermediate. Krasnova [11] reported that the introduction of chloroform favored the generation of dichlorosilylene. It is dubious whether dichlorosilylene serves as another important intermediate.…”