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Starting from (+)‐camphor‐10‐sulfonyl chloride (5), the crystalline sultam 8 was easily prepared. Lewis‐acid‐promoted Diels‐Alder additions of the crystalline N‐acry‐loyl and N‐crotonoyl derivatives 9 and 10, respectively, to cyclopentadiene and 1,3‐butadiene at −130 to −78° furnished adducts 11, 12 and 17 with high chiral efficiency. Crystallization of the adducts and nondestructive removal of 8 gave either alcohols 13, 14 and 18 ir acid 19 in 99% enantiomeric purity. The sense of induction was reversed on using the enantiomer of 8 as the auxiliary. The structure of 10 was established by X‐ray diffraction analysis.

In connection with structure-activity relationship studies, analogues of campholenal ((+)-4b), an important building block for sandalwood-like odorants, were prepared. The five-membered-ring analogues 4 were obtained by epoxidation of the corresponding a -pinene derivatives 2, followed by catalytic ZnBr, isomerisation (Scheme 2). The six-membered-ring skeleton was obtained by ozonolysis of a -campholenyl acetate ((-)-14b), followed by intramolecular aldol condensation (Scheme 5 ) . I3C-NMR assignments are given.

Comparative semi‐empirical PM3 and ab initio STO 3‐21G calculations on bornanesultam‐derived dienophiles containing the structural moiety SO2NC(O)X(α) = Y(β) suggest that, among the conformers of low energy, the thermodynamically less stable SO2/C(O)‐syn,C(O)/X=Y‐s‐cis conformation is also reactive in terms of LUMO level and atomic coefficients. Furthermore, the X(α), Y(β) LUMO atomic coefficients are nonequivalent with respect to both X(α)‐re and X(α)‐si faces, and thus have, depending on the conformation, a matching or mismatching stereoelectronic influence with the co‐operative steric effect. This dissymmetry is believed to result from the generalized anemone effect of the N lone pair, itself anomerically stabilized and directed, in the absence of crucial steric interactions, by the pseudo‐axial anti‐periplanar SO bond. Five N‐acyl‐substituted bornanesultams arc discussed ((–)‐1a: N‐acryloyl, XCH, YCH2; (–)‐1b; N‐crotonoyl, XCH, YCHMe; (–)‐1c: N‐N′‐fumaroyl, XCH, YCH(C(O)‐bornanesultam); 2a: N‐glyoxyloyl, XCH, YO; 2b: N‐acylnitroso, XN, YO). In this context, differences with toluenesultams 3 are pointed out. A previous report on N‐(acylnitroso)‐bornanesultam 2b is revisited, and the diastereoselectivity observed is shown to result from thermodynamic control.

Dynamic mixtures of aminals generated by reversible reaction of diamines with volatile aldehydes and ketones are suitable delivery systems to increase the long‐lastingness of fragrance perception in functional perfumery applications. N‐Heteroarylmethyl‐substituted secondary diamines of 1,2‐diaminocyclohexane, 1,3‐diaminocyclohexane, 1,2‐diaminoethane, 1,2‐diaminopropane, 1,3‐diaminopropane or 2‐(aminomethyl)piperidine were prepared by reaction with furan‐, 1H‐pyrrole‐, thiophene‐ or pyridine‐2‐carbaldehyde and reduction of the intermediate imines with NaBH4. The performance of the delivery system was evaluated in a fabric softener application in the presence and absence of a diamine by following the evaporation of a mixture of 18 fragrance aldehydes and ketones on dry cotton using dynamic headspace analysis. Equilibration of the mixture in the presence of a diamine simultaneously increased the headspace concentrations of several fragrance raw materials above the cotton surface as compared to a reference sample without diamine. Equilibrated dynamic mixtures of diamines were found to be suitable delivery systems to prolong the evaporation of fragrance aldehydes and ketones in practical applications of functional perfumery. Copyright © 2013 John Wiley & Sons, Ltd.

α‐, β‐, and γ‐Irones and analogues have been prepared from optically active ketones (+)‐1, (+)‐6a,b, and (+)‐17, via a Corey‐Chaykovsky oxiranylation (Me2S, Me2SO4, Me2SO, NaOH) followed by isomerisation (SnCl4 or MgBr2). (+)‐Dihydrocyclocitral (19a), obtained from (−)‐citronellal, and analogue (+)‐19b, were condensed with various ketones to afford (+)‐21a–f, and after hydrogenation (+)‐22a–f. A mild oxidative degradation of aldehydes (+)‐trans‐and (−)‐cis‐8a,b, to ketones (−)‐16a,b, as well as olfactive evaluations, 13C‐NMR assignments, and absolute configurations of the intermediate epoxides, aldehydes, and alcohols are presented.

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