98 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS Table II Conversion Ratios of Dials to Acetals (GLC) Dial Acetal reactions (%) (1) 98 (4) 97 (9) 99 and finer than those of the starting reagents. We conclude that the introduction of gem-diester functions into these terpenes provides several new compounds possessing odor properties that could be of use to the fragrance industry. EXPERIMENTAL SPECTROSCOPIC AND GAS CHROMATOGRAPHIC STUDIES Infrared spectra were measured on a Schimadzu IR-400 Model Spectrophotometer, and •H-NMR spectra were recorded by a Bruker 200 MHz Model instrument using TMS as CH2 addition allylic insertions allyl rearrangement ins. (8) CH 3 CH3 X2HC '-.% addition (8) allylic insertions X'CO2CH 3 /•OHX2 HaO'/•'-OX2H allyl rearrangement insertions Scheme 5

NEW ODOROUS TERPENES 99 an internal standard. Gas chromatogrophic studies were performed on a Schimadzu instrument, Model 5A, equipped with an F.I.D. detector. OV-17 3% on Chromosorb w 100/120 mesh, 3 mm. ID. X 3 m column was used. The following conditions were imposed: injection and detector temperature: 250ø carrier gas (N2): 55 ml/min tem- perature: isothermal at 165ø integrator: ITG-4A. Reproducibility of results was -T-0.5% under the same conditions. Internal standards were used for calculation. Three runs were carried out in each case. Elemental analyses were performed on Hereaeus Microstandard equipment. PREPARATIVE THIN-LAYER CHROMATOGRAPHY STUDIES (P-TLC) P-TLC studies were carried out using Silicagel HF254 layers (1 mm). Solvents were CH2Cl•:CC14:n-hexane:ethylacetate (75:10:10:5) and iso-octane:iso-amylacetate (85:15). As detection spray (for pattern plate only), 3.5% ethanolic solution of phos- phomolybdic acid was used. INITIAL MATERIALS AND STANDARDS In our previous papers, we had synthesized some of the compounds related to this study (18-19). Dimethyldiazomalonate (starting from p-toluene sulphonylazide), carbene dimers (tetramethoxycarbonylethane and tetramethoxycarbonylethylene) were prepared by the method of Wulfman and co-workers. (IS)-(-) [3-pinene and 'y-terpinene (Fluka) were ca. 95%, and R(•-)-p-menth-l-ene (Fluka) was 99% in purity. GENERAL PROCEDURE FOR THE REACTIONS WITH dmdm A solution of 0.07 mol of Cu(acac) 2 in 0. 125 mol olefin was refluxed, while a solution of 0.01 mol of dmdm in olefin (0. 125 mol) was added dropwise (ca. six drops per minute). After completion of dmdm addition, samples taken from the continuing reac- tion at time intervals were analyzed by GLC and IR in order to ensure the end of the reaction. The mixture was filtered while hot, and the excess olefin was recovered by vacuum distillation. The residue was analyzed by GLC and p-TLC. The zones that could be extracted from p-TLC were recontrolled by GLC to ensure their purities, and only pure fractions were identified by IR, 1H-NMR, and elemental analysis. GENERAL PROCEDURE FOR THE SYNTHESIS OF Cis-DIOLS While olefin (0.08 mol), glacial acetic acid (320 ml), and silver acetate (0.2 mol) were vigorously stirred at room temperature, iodine (0.17 mol) was added portionwise for over 1.5 hours. Water (1 ml) was then added to the reaction mixture, which was heated for 4 hours on a water bath while being stirred. AgI was filtered off after cooling the reaction mixture, and the tiltrate was evaporated in vacuo to remove acetic acid and unreacted olefin. The residue was hydrolyzed by heating with 10% ethanolic KOH solution for one hour (pH 11.5). The resulting mixture was diluted with water and extracted successively with n-hexane-ether (1:1) mixture. The solvent was removed and diols were crystallized from n-heptane.