A new route to cumulenes by stannylation-deoxystannylation of propargylic alcohols. Application to synthesis of conjugated enyne[3]cumulene as a model compound of neocarzinostatin chromophore

Article abstract of DOI:10.1016/S0040-4039(98)01117-4

Sequential treatment of a propargylic alcohol by BuLi and Bu₃SnCl gave a mixture of stannylated propargylic alcohol and stannylated allenyl alcohol, both of which were converted to a single [3]cumulene by deoxystannylation of the stannyl alcohols by treatment with methanesulfonyl chloride and triethylamine. The efficiency of the deoxystannylation has been compared with that of an analogous silyl counterpart and proved to be much more efficient. The method has been applied to synthesis of conjugated enyne[3]cumulene 3 as a model compound of neocarzinostatin chromophore.