The stereochemically controlled synthesis of spirocyclic ethers and lactones with medium-sized (7-, 8-, and 12-membered) carbocyclic rings by phenylthio migration: 1-oxaspiro[4. n]alkanes and alkan-2-ones with N = 6, 7, and 11

Article abstract of DOI:10.1016/S0040-4039(00)61701-X

3-Methyl-4-phenylthio-1-oxaspiro[4.6]undecanes, [4.7]dodecanes, [4.11]hexadecanes and the corresponding 2-ones (lactones) can be made from cyclohepta-, octa-, and dodecanone by chain extension to the 2-phenylthio-carbaldehyde, stereoselective aldol reacti