Synthesis of 4-(alkoxyamino)chroman-2-ones via 6-exo-trig cyclization of carbon-centered radicals into oxime ethers
作者:Carlos A. Bejarano、John E. Díaz、Alix E. Loaiza
DOI:10.1007/s10593-016-1857-z
日期:2016.3
synthesized via a 6-exo-trig cyclization of alkyl radicals obtained from α-bromoesters containing an oxime ether group. In the case of secondary bromides, the best results were achieved using tris(trimethylsilyl)silane as the chain transfer agent and Et3B as the initiator in dichloromethane at room temperature; the corresponding chromanones were produced in 58–70% yield. Low yields of the cyclized compounds