Transformation of Esters into 2‐Substituted Allyl Halides via Tertiary Cyclopropanols: Application in the Stereoselective Synthesis of (2S,3S,7S)‐3,7‐Dimethyl‐2‐pentadecyl Acetate, the Sex Pheromone of the Pine Sawfly Neodiprion sertifer

Abstract

(2S,3S,7S)-3,7-Dimethyl-2-pentadecyl acetate (ac-1), the sex pheromone of the pine sawfly Neodiprion sertifer, has been newly synthesized by the transformation of the corresponding esters 8 and 12 into 2-oxyalkyl-substituted allyl bromides 4 and 5 via tertiary cyclopropanols 6 and 7.

Asymmetric Olefin Isomerization of Butenolides via Proton Transfer Catalysis by an Organic Molecule

“…The isomerization of these butenolides proceeded with a lower yet still useful level of enantioselectivity. In light of the lack of an efficient approach toward optically active β,γ-disubstituted α,β-butenolides, ,, the current isomerization represents a valuable access toward these chiral building blocks.…”

The Kulinkovich hydroxycyclopropanation reaction in natural product synthesis

“…Diprionol 61 and its acetate 62 which is the major component of the sex pheromone of the pine sawfly Neodiprion sertifer was synthesised stereoselectively by Kulinkovich et al 42 by conversion of mesylated cyclopropanols into allyl halides which had previously been used successfully for the synthesis of the sex attractants of Diprion pini (Scheme 17). The two chiral building blocks for the synthesis of the acetate 62 were both synthesised from allyl halides 55 and 59 which were prepared from the corresponding cyclopropanols 54 and 58, respectively.…”

New synthesis of syn-stereodiad building block for polyketides. Formal synthesis of arenamides A and C

“…Taking into account broad spectrum of biological activity of arenamides and keen interest of our research team in total and formal syntheses of natural compounds from hydroxy esters [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31], a novel procedure has been developed for the preparation of protected (3S,4S)-3-hydroxy-4-methyldecanoic acid 2 which is the most complex molecular fragment of macrolides 1a-1c (Scheme 1). The starting compound for the synthesis of 2 was (7S)-7-(3-bromoprop-1-en-2-yl)-5,5-dimethyl-4,6-dioxaspiro [2.5]octane (4).…”