Structure–Activity Relationship in the Domain of Odorants Having Marine Notes

Abstract

We synthesized or re-synthesized a large series of 2H-1,5-benzodioxepin-3(4H)-ones 9 (Scheme 1), 4,5-dihydro-1-benzoxepin-3(2H)-ones 10 (Schemes 3 and 4) and 5,6,8,9-tetrahydro-7H-benzocyclohepten-7-ones 11 (Schemes 5 and 6), since the lead compound for the olfactory note of perfumes based on marine accords is a well-known benzodioxepinone named Calone 1951 (9b). We meticulously described the odor profile of each synthesized compound and discussed relevant structure -odor relationships (Tables 1 -3). In particular, we revealed a correlation between the conformation of the seven-membered ring and the activities of these compounds (Table 4 and Fig. 3). We also clarified the effect of the position and the size of the alkyl substituent at the aromatic ring.

1,3-Dichloroacetone

“…[11][12][13][14][15][16][17] Significantly, the unique examples cited in literature of the use of 1,3-dichloroacetone with aromatic amines entail reactions with highly nucleophilic ambident amines (e.g., 2-aminopyridine). [18][19][20] (D) The activation of the carbonyl moiety by an acid allows the addition to the carbonyl carbon of a suitable nucleophile (hydroxylamine derivatives 21 or diols).…”

Structure–Activity Relationships in the Domain of Odorants Having Marine Notes

“…This domain was later revisited, [2][3][4][5][6][7][8][9][10][11] and now compounds such as Transluzone (1b), Aldolone ® (1c), and Azurone ® (1d) are produced on a ton scale by Firmenich and Givaudan, and used in fine fragrance as well as in body-and home-care products (e.g., shower products, air fresheners, and powder detergents).…”

Marine Fragrance Chemistry

“…For Calone 1951, Gaudin et al calculated that the pseudo-twist boat conformation (0 kcal/mol; Fig. 5) to be energetically more stable than the pseudohalf chair ( þ 2.7 kcal/mol) conformation with a near-coplanar arrangement of the CO group and the benzene ring, whereas the deoxygenated and ketone modified derivatives preferably adopted the pseudo-half chair conformations [3]. The conse- Chemical Synthesis.…”

“…-Differences in odor analysis, GC -olfactometry vs. blotting techniques, and evidence of the subjective and subtle nature of fragrance characterization led to different fragrance profiles. The C(6)ÀMe isomer of Calone 1951 was evaluated by Givaudan perfumers 1 ) to contain a fresh, floral-aldehydic, green, and woody marine tonality, whereas Gaudin et al perceived phenolic, earthy elements with some marine in the base note [3]. The introduction of non-alkyl functional groups such as C(6)ÀMeO, C(7)ÀNO 2 , C(7)ÀCHO, or naphthyl for phenyl group replacement, as presented in Table 3 Molecular Frontier vs. Marine Fragrance.…”