116262-03-4Relevant academic research and scientific papers
Asymmetric Acetalization: A Simple Method for the Synthesis of Chiral α-Monosubstituted Cyclopentanones
Nishida, Mayumi,Nakaoka, Kazuyo,Ono, Shizuka,Yonemitsu, Osamu,Nishida, Atsushi,et al.
, p. 5870 - 5872 (1993)
Acetalization of α-monosubstituted cyclopentanones with chiral hydroxy thiols under equilibrating conditions afforded a mixture of acetals in a highly diastereoselective manner, and deacetalization of the product affords optically active α-monosubstituted cyclopentanones.
Enantioselective protonation of prochiral enolates with chiral imides
Yanagisawa, Akira,Kikuchi, Tetsuo,Kuribayashi, Takeshi,Yamamoto, Hisashi
, p. 10253 - 10264 (2007/10/03)
New chiral proton sources possessing an asymmetric 2-oxazoline ring, (S,S)-imide 1 and related imides, were synthesized from Kemp's triacid and optically active 2-amino alcohols. With these chiral imides, various lithium enolates of α-monoalkylated cycloalkanones were effectively protonated with excellent to moderate enantioselectivity. An increase in enantioselectivity was observed in the asymmetric protonation of prochiral enolates with (S,S)- imide 1 using lithium salt as an additive. For example, (R)-enriched 2-n- pentylcyclopentanone 35 was obtained in high yield with 90% ee when the silyl enol ether 33 was treated with n-BuLi in the presence of 5 equiv of LiBr in Et2O, and the resulting lithium enolate 34 was then protonated by a solution of (S,S)-imide 1 in THF. In contrast, the product 35 obtained without LiBr exhibited a lower enantiomeric excess (74% ee).
Enantioselective Synthesis of (R)-(+)-5-Hexadecanolide, the Pheromone of Queen of Oriental Hornet, Vespa orientalis Linn
Gadkari, R. G.,Kapadi, A. H.
, p. 814 - 815 (2007/10/02)
An enantioselective synthesis of (R)-(+)-5-hexadecanolide (1) using cyclopentanone, and (R)-2-aminobutyl-n-undecyl iodide (as electrophile) is reported.
