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Struktur und Geruch, XIII. Synthese und olfaktorische Eigenschaften von Megastigmatrienon‐Analoga
Author(s) -
Weyerstahl Peter,
Meisel Thomas,
Mewes Klaus,
Negahdari Shoreh
Publication year - 1991
Publication title -
liebigs annalen der chemie
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.825
H-Index - 155
eISSN - 1099-0690
pISSN - 0170-2041
DOI - 10.1002/jlac.199119910104
Subject(s) - chemistry , odor , isophorone , ketone , dehydration , intramolecular force , stereochemistry , medicinal chemistry , organic chemistry , catalysis , biochemistry
Structure–Odor Correlation, XIII 1) . – Synthesis and Olfactive Properties of Megastigmatrienone Analogues The key compound 9 was readily prepared in larger quantities by an improvement of a known procedure. Addition of carbanions to the unprotected ketone 9 gives the hydroxy ketones 16–21 via the acetals 10–15 . Dehydration of 16–20 furnishes the dienones 2–6 while 7 is available in fair yield via the acetoacetate 21 . Through intramolecular cyclization also the ester 26 is formed which affords with NaOH the keto ester 29 by a retro‐Michael reaction. The diketone 28 (obtained from 29 ) can be reduced selectively to give 30 , dehydration of which leads to 31/32 . – The odor of 2 (camphor, sweet, wood, plum) is the olfactive link between the odor of isophorone and megastigmatrienone ( A ). Elongation of the alkyl group (→ 3–5 ) leads first to a herbaceous, then to a leathery note. The one‐diene‐one 7 smells unexpectedly weak. For the very strong odor (tobacco, wood, plum) of A obviously the total osmophor is responsible including the unsaturated side chain.