Sg. Kim et al., GENERATION AND REACTION OF CARBENES FROM ALPHA-OXACYCLO-N-AZIRIDINYL IMINES - A NEW METHOD FOR RING EXPANSION OF CYCLIC ETHERS, Chemical communications, (8), 1996, pp. 909-910
alpha-Oxetanyl-N-aziridinyl imines undergo ring expansion on heating t
o afford dihydrofurans via alkylidenecarbenes, whereas heating alpha-t
etrahydrofuranyl and alpha-tetrahydropyranyl N-aziridinyl imines affor
ds the ring expanded cyclic enol ethers via alkyl carbenes.