Isothiocyanates, bismuthonium ylide

The reaction of the same bismuthonium ylide with isothiocyanates in the presence of a copper(H) catalyst afforded the sulfur-incorporated spiro-cyclic compound as the main product, in addition to a small amount of carbon-carbon bond formed products (Scheme 12) [28],... 

Scheme 12 Reaction of bismuthonium ylide with isothiocyanates...

In a few cases this reaction gives ylides of PhaP and PhsAs, albeit in relatively low yield. In combination with isothiocyanates, some bismuth ylides yield complicated addition products, although the fate of the bismuth atom in these reactions is not determined. Likewise, bismuthonium compounds are finding a growing utility in organic synthesis d. 

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