Other Reactions of Organolithiums

Sonolysis of the dichloride with lithium in THF was reported to give a 90% yield of the novel silylene. Unfortunately, these results proved irre-producible and Masamune later pointed out that the product generally obtained is the cyclic structure (12) [103]. 

Reaction was complete within 5 min. In comparison, the stirred reaction takes ten times as long [104]. Alkylation of diphenylphosphines could also be readily achieved to give high yields of uncontaminated product. Previous routes to these important chelating agents had suffered from the extreme sensitivity of the secondary phosphines to air and the difficulty of its exclusion over the long periods of time necessary to obtain satisfactory yields of product. 

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