Unprecedented Rearrangement of β-Difluoroboryloxy Ethers: A Route to C-2 Alkyl-chromenones

The addition of boron trifluoride etherate (BF3 center dot OEt2) to allenic ketones has led to the isolation of the isolated boron difluoride enolates. The single-crystal structure of boron enolate has been solved. The unprecedented C-1-C-10 migration of (Z)-beta-difluoroboryloxy ether derivatives is observed to deliver rearranged phenol derivatives which are functionalized to C-2 alkyl-chromenones. Interestingly the isolated boron enolates have exhibited significant anticancer properties.

Automated summary

The addition of boron trifluoride etherate to allenic ketones resulted in the isolation of isolated boron difluoride enolates, whose crystal structure has been determined. The migration of (Z)-beta-difluoroboryloxy ether derivatives from C-1 to C-10 has been observed, leading to rearranged phenol derivatives that can be further functionalized into C-2 alkyl-chromenones. Interestingly, the isolated boron enolates show significant anticancer properties.