γ‐Unsaturated Aldehydes as Potential Lilial Replacers |
| |
Authors: | Martin Schroeder Marion Mathys Nadja Ehrensperger Michelle Büchel |
| |
Affiliation: | 1. Givaudan Schweiz AG, Fragrance Research, überlandstrasse 138, CH‐8600 Dübendorf, (phone: +41?44?824?22?43;2. fax: +41?44?824?29?26) |
| |
Abstract: | A series of Claisen rearrangements was undertaken in order to find a replacement for Lilial (=3‐(4‐(tert‐butyl)phenyl)‐2‐methylpropanal), a high‐tonnage perfumery ingredient with a lily‐of‐the‐valley odour, which is a CMR2 material [1]. 5,7,7‐Trimethyl‐4‐methyleneoctanal ( 10 ), the synthesis of which is described, became the main lead. It possesses an odour which is very close to that of Lilial but lacks its substantivity. Aldehydes with higher molecular weights than that of 10 were, therefore, synthesised in order to boost substantivity and to understand the structural requirements for a ‘Lilial’ odour. The aldehydes were obtained via Claisen rearrangements of ‘exo‐methylidene’ vinyl ethers, allenyl vinyl ethers, or allenyl allyl ethers. Alternatively, coupling of terminal alkynes with allyl alcohols led to the desired aldehydes. Derivatives of 10 and their sila analogues were also synthesised. The olfactory properties of all synthesised molecules were evaluated for possible structure? odour relationships (SOR). |
| |
Keywords: | Muguet Odorants Claisen rearrangement Sila substitution Structure odor relationship (SOR) |
|
|