SYNTHESIS OF ALL OF THE FOUR ENERGETICALLY POSSIBLE STEREOISOMERS OF 7-ETHYL-2-METHYL-1,6-DIOXASPIRODECANE; A PHEROMONE PRODUCED BY BEES PARAVESPURA VULGARIS L. AND ANDRENA HAEMORRHOA F.

Article abstract of DOI:10.1016/S0040-4020(01)91498-X

All of the four energetically possible stereoisomers<(2R,5R,7R)-, (2R,5S,7S)-, (2S,5R,7R)- and (2S,5S,7S)- isomers> of 7-ethyl-2-methyl-1,6-dioxaspiro<4.5>decane were synthesized starting from ethyl (S)-lactate and dimethyl (S)-malate or methyl (R)-β-hydroxy-valerate employing dianion alkylation as the key-step.