12-nor-alloisolongifolan-11-one, a ketone with amber-like odour from longifolene

Abstract

Acid-catalysed isomerization of longifolene 1 gives alloisolongifolene 2 which, after ozonolysis, creates ketone 3 with a rich, earthy and amber-like odour. #

Odds and Trends: Recent Developments in the Chemistry of Odorants

“…Ambery and tobacco facets are indeed present in the odor profile of 179, but these are astonishingly accompanied by a fruity, a-damascone note. From a molecular [104,105] and the recently published [106] 12-noralloisolongifolan-11-one (189, Scheme 38. The cyclic ether Ambrox (7) remains the prototype of what perfumers understand as ambery, which is actually a very unclear term derived from the multifacet odor of natural ambergris.…”

Characteristics of some synthetic terpenoids with a grapefruit odour discovered by serendipity

“…Figure 1 shows several (3)(4)(5)(6)(7)(8) commercial compounds of a similar grapefruit odour but with a different functional group. [8] Earlier in our laboratory two valuable terpenoid odour compounds with the musk [9,10] and ambergris [11] scent were discovered by serendipity. Currently, the aim is to design structures with assumed odoriferous properties based on existing ones; a good example of this kind of approach are the recent works of Philip Kraft et al [5][6][7] Owing to currently still limited knowledge on odour perception, research to find new compounds has become more challenging and can lead to extremely valuable discoveries that, consequently, stimulate studies on understanding olfaction.…”

Allerlei Trends: die neuesten Entwicklungen in der Riechstoffchemie

“…Tatsächlich sind Ambra-und Tabakfacetten im Geruchsprofil von 179 vorhanden, aber sie werden erstaunlicherweise von einer fruchtigen a-Damasconnote begleitet. Aus Sicht des Molecular Modelings ist es interessant, die Formen der Moleküloberfächen des Propellans 186, das durch eine interessante säurekatalysierte Umlagerung aus Sclareolid 184 erhalten wurde, [104,105] und des vor kurzem veröffentlichten [106] 12-Noralloisolongifolan-11-ons 189 (erhalten aus Longifolen 187) mit denen der Holz-Riechstoffe Iso E Super 166, Georgywood 170 und deren Analoga (siehe Abschnitt 7.4) zu vergleichen. Der cyclische Ether Ambrox 7 bleibt der Prototyp für das, was der Parfümeur normalerweise unter ambraartig versteht, ein eigentlich sehr schwammiger Begriff, der sich vom facettenreichen Geruch der natürlichen grauen Ambra ableitet.…”