Lipase-mediated partial resolution of 1,2-diol and 2-alkanol derivatives: towards chiral building-blocks for pheromone synthesis

1,2-Propanediol 5,1-chloro-2-propanol 8 and its related 2-O-acetate 9 were partially resolved by chemoenzymatic acetylation and deacetylation, in the presence of Pseudomonas fluorescens lipase (Amano P.; PFL), to (R)-(-)-1-ac etoxy-2-propanol 6, (R)-(+)-2-acetoxy-1-chloropropane 9 and (R)-(-)-1-chlor o-2-propanol 8, respectively. On the other hand, treatment of (2RS)-2 with vinyl acetate in ether and Chirazyme(R) L-2 gave 2-O-acetyl-1,3,4-trideoxy- 5,6:7,8-di-O-isopropylidene-beta-D-manno-non-5-ulo-5,9-pyranose 1 and 1,3,4 -trideoxy-5,6:7,8-di-O-isopropylidene-beta-D-gluco-non-5-ulo-5,9-pyranose 1 1, respectively. Compound 10 was subsequently deacylated to 12. Both alcoho ls 11 and 12 were treated with Me2CO/H+ to cause their rearrangement to (2S ,5R,8R,9R, 10S)-10-hydroxy-8,9-isopropylidenedioxy-2-methyl-1,6-dioxaspiro[ 4.5]decane 3 and its (2R)-epimer 4, which closely matched the skeleton of t he odour bouquet minor components of Paravespula vulgaris (L.). (C) 2000 El sevier Science Ltd. All rights reserved.