M etherdiethyl ether, affording the crude compounds three and four, respectively.(E)-3,7-dimethyl-8-oxoocta-1,6-dien-3-yl-acetate (4), 8-oxolinalyl AcetateFollowing GP1,

M etherdiethyl ether, affording the crude compounds three and four, respectively.(E)-3,7-dimethyl-8-oxoocta-1,6-dien-3-yl-acetate (4), 8-oxolinalyl AcetateFollowing GP1, from two (5 g, 25 mmol) and selenium dioxide (two.7 g, 25 mmol) in 15 ml dioxaneethanol 9:1 (vv), compound four was prepared. Flash chromatographic purification with petroleum etherdiethyl ether three:2(vv) yielded 1.4 g (29 ) of 4 as orange oil.1 H NMR (600 MHz, CHLOROFORM-d) ppm 9.39 (1 H, s), 6.44.50 (1 H, m), five.96 (1 H, dd, J = 17.56, 11.14 Hz), 5.15.26 (two H, m), 2.37 (2 H, q, J = 7.93 Hz), two.06.12 (1 H, m), two.02 (3 H, s), 1.87.95 (1 H, m), 1.74 (three H, s), 1.59 (3 H, s).13 C NMR (151 MHz, CHLOROFORM-d) ppm 195.1, 169.9, 153.7, 141.1, 139.five, 113.8, 82.three, 38.1, 23.79, 23.79, 22.1, 9.12. MS (EI) mz(rel.int.): 210 [M+ ] (1), 150(18.38), 135(14), 121(19), 107(18.05), 93(26), 82(41), 71(46), 55(29), 43(one hundred).(E)-3,7-dimethyl-8-oxoocta-1,6-dien-3-ol (three), 4-Epianhydrotetracycline (hydrochloride) Formula 8-oxolinaloolFollowing GP1, from 1 (4.eight g, 31.1 mmol) and selenium dioxide (three.four g, 30.four mmol) in 30 ml dioxaneethanol 9:1 (vv), compound 3 was prepared. Flash chromatographic purification with petroleum etherdiethyl ether 1:4 (vv) yielded 1.4 g (29 ) of 3 as orange oil.1 H NMR (600 MHz, CHLOROFORM-d) ppm 9.38 (1 H, s), six.42.56 (1 H, m), 5.92 (1 H, dd, J = 17.26, 10.67 Hz), five.25 (1 H, dd, J = 17.26, 0.91 Hz), 5.11 (1 H, dd, J = 10.90, 0.91 Hz), 2.35.45 (2 H, m), 1.74 (3 H, s), 1.61.71 (2 H, m), 1.31.35 (three H, m).13 C NMR (91 MHz, CHLOROFORMd) ppm 195.2., 154.six, 144.three, 139.2, 112.4, 72.9, 40.three, 28.1, 23.8, 9.1.MS (EI) mz(rel.int.): 168 [M+ ] (1), 98(15), 87(27), 82(24), 71(100), 55(33), 43(58), 41(23).Process two (E)-8-hydroxy-3,7-dimethylocta-1,6-dien-3-yl-acetate (5), 8-hydroxylinalyl AcetateCompound 4 (800 mg, three.81 mmol) was dissolved in dry methanol (40 ml) and sodium borohydride (NaBH4 ; 1.eight g, 4.72 mmol) was added (Liu et al., 2003; Scheme two). The option was allowed to stir at -10 C. Immediately after 1 h, water was added as well as the reaction mixture was extracted with dichloromethane (DCM). The organic layer was dried more than sodium sulfate. Following removal with the solvent, the residue was subjected to flash chromatography eluted with petroleum etherdiethyl ether 2:3 (vv) and yielded 626 mg (77 ) of 5 as light yellow oil.1 H NMR (360 MHz, CHLOROFORM-d) ppm five.97 (1 H, dd, J = 17.48, 10.90 Hz),SCHEME two | Synthetic pathways for the synthesis of linalool and linalyl acetate oxygenated derivatives following procedures 1-4.Frontiers in Chemistry | www.frontiersin.orgOctober 2015 | Volume 3 | ArticleElsharif et al.Structure-odor relationships of linalool and derivatives5.36.43 (1 H, m), five.15 (two H, dd, J = 17.48, 11.13 Hz), three.99 (two H, d, J = 5.45 Hz), two.03.09 (two H, m), two.01 (three H, s), 1.75.96 (2 H, m), 1.66 (3 H, s), 1.55 (three H, s). 13 C NMR (91 MHz, CHLOROFORM-d) ppm 169.9, 141.7, 135.two, 125.four, 113.three, 82.eight, 68.8, 39.four, 23.7, 22.two, 21.9, 13.6. MS (EI) mz(rel.int.): 211 [M+ -1] (1), 134(7), 119(27), 93(46), 79(35), 67(30), 55(24), 43(100).182 [M+ -2] (1), 151(4), 138(7), 121(15), 111(14), 103(16), 95(16), 82(11), 71(one hundred), 67(18), 55(24).(E)-6-acetoxy-2,6-dimethylocta-2,7-dienoic-acid (8), 8-carboxylinalyl AcetateFollowing GP4, compound 4 (0.three gm, 1.24 mmol) was dissolved in 25 ml tert-butyl alcohol and six ml 2-methyl-2-butene. A answer of sodium chlorite (1.08 gm, 11.4 mmol) and sodium dihydrogenphosphate (1.05 gm, eight.55 mmol) in 10 ml water was added dropwise more than a 10 min period, compound eight was prepared. Flash chromatographic purification with ethyl acetatemetha.