which upon treatment with trifluoroacetic acid gave the chiral lactone 42. The
S configuration of lactone 42 was established by converting it to the naturally
occurring pheromone (R)-(+)-5-hexadecanolide 12. Thus, acylation of the free
amine, reduction of the lactone, and subsequent treatment with acid gave lactone
43, which upon oxidation of the primary alcohol to aldehyde, Wittig reaction, and
hydrogenation provided the pheromone 12.
An example related to the formation of δ-lactone from a δ-hydroxy ortho ester
derivative has been demonstrated by Carretero and Ghosez in the synthesis of
(À)-argentilactone [44], an α,β-unsaturated δ-lactone [45] (Scheme 8). A normal
Scheme 6 Giese and Gerth synthesis of δ-lactones
Scheme 7 Oda et al. synthesis of (R)-(+)-5-hexadecanolide
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K. Palanichamy and K.P. Kaliappan
S configuration of lactone 42 was established by converting it to the naturally
occurring pheromone (R)-(+)-5-hexadecanolide 12. Thus, acylation of the free
amine, reduction of the lactone, and subsequent treatment with acid gave lactone
43, which upon oxidation of the primary alcohol to aldehyde, Wittig reaction, and
hydrogenation provided the pheromone 12.
An example related to the formation of δ-lactone from a δ-hydroxy ortho ester
derivative has been demonstrated by Carretero and Ghosez in the synthesis of
(À)-argentilactone [44], an α,β-unsaturated δ-lactone [45] (Scheme 8). A normal
Scheme 6 Giese and Gerth synthesis of δ-lactones
Scheme 7 Oda et al. synthesis of (R)-(+)-5-hexadecanolide
102
K. Palanichamy and K.P. Kaliappan