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dissolved in 20 mL of THF is slowly added within 1 h to a well-stirred suspension of SmCp2 (10 mmol) in THF (150 mL) at -20 °C.A brown suspension is obtained.A solution of 4.16 mmol of aldehyde in 5 mL of THF is quickly added.The reaction mixture turns immediately yellow.After 2 h, the solution is treated as previously.Pure a-ketol is analyzed by GC, GC/MS, and *H NMR spectroscopy.In another series of experiments (Barbier-type conditions), acid chloride (4.16 mmol) and aldehyde (4.16 mmol) are mixed together in THF (5 mL) and added to a suspension of SmCp2 (10 mmol) in THF (150 mL) at -20 °C.2.2-Dimethyl-4-hydroxy-3-decanone: *H NMR b 4.5 (m, 1 H), 3.3 (m, 1 H), 1.6 (m, 10 H), 1.20 (s, 9 H), 0.95 (t, J = 7.8 Hz, 3 H); 13C NMR b 217.9, 72.3, 42.5, 34.8, 31.6,29.0, 26.7, 25.0, 22.5, 13.9; MS 200 (0.4) M+, 115 (26.2) C6H13CHOH, 97 (65.7)C7H13, 85 (6.1) i-BuCO, 57 (100) i-Bu.Anal.Calcd for C12H2 402: C, 71.95; H, 12.08.Found: C, 71.69; H, 11.85.3.3-Dimethyl-l-hydroxy-l-phenyl-2-butanone: !H NMR b 7.3 (m, 5 H), 5.4 (s, 1 H), 4.4 (m, 1 H), 1.05 (s, 9 H); MS 192 (0.4) M+, 164 (7.4) M-CO, 107 (100) C6H6CHOH, 77 (31) C6H5, 57 (51.1) f-Bu.Anal.Calcd for C12H160 2: 74.97; H, 8.38.Found: C, 74.78; H, 8.20.2,2-Dimethyl-4-hydroxy-3-hexanone: *H NMR 5 4.5 (m, 1 H), 3.6 (m, 1 H), 1.6 (m, 2 H), 1.2 (s, 9 H), 0.95 (t, J = 7.9 Hz, 3 H); MS 144 (0.6) M+, 88 (4.0), 69 (2.7), 57 (100) i-Bu.Anal.Calcd for C8H160 2: C, 66.63; H, 11.18.Found: C, 66.58; H, 11.38.l-Adamantyl-2-hydroxy-l-butanone: !H NMR b 4.45 (t + s, 1 H), 3.3 (m, 1 H), 1.75 (m, 17 H), 0.9 (t, J = 8.1, Hz, 3 H); MS 222 (3.16) M+, 193 (0.58) AdCOCHOH, 163 (5.42) AdCO, 135 (100) Ad; IR 3478, 1695, 1452, 1403, 1381.Anal.Calcd for C14H220 2: C, 75.63;H, 9.97.Found: C, 75.50;H, 9.76.l-Adamantyl-2-hydroxy-2-phenylethanone: *H NMR b 7.35 (m, 5 H), 5.4 (s, 1 H), 4.4 (s, 1 H), 1.6 (m, 15 H); MS 270 (0.3) M+, 163 (13.1)AdCO, 107 (12.9)PhCHOH, 77 (17.9)Ph.Anal.Calcd for C18H220 2: C, 80.00; H, 8.15.Found: C, 80.08; H, 8.02.l-Cyclohexyl-2-hydroxy-l-butanone: *H NMR b 4.31 (m, 1 H), 3.40 (m, 1 H), 2.38 (m, 1 H), 1.6 (m, 12 H), 0.93 (t, J = 8.4 Hz, 3 H); MS 170 (1.50) M+, 111 (19.5)C6Hn CO, 83 (100) cyclohexyl, 59 (35.5)CH3CH2CHOH; IR 3320,1708,1453,1417,1314.Anal.Calcd for C10H18O2: C, 70.55; H, 10.66.Found: C, 70.59; H, 10.81.2-Hydroxy-l-(l-methylcyclohexyl)-l-butanone: *H NMR b 4.5 (m, 1 H), 1.95 (m, 3 H), 1.5 (m, 10 H), 1.2 (s, 3 H), 1.0 (t, J = 8.8 Hz, 3 H); 13C NMR b 218.0, 73.4,46.7, 34.7, 34.1, 28.1, 25.6, 23.7, 22.5, 22.3, 9.3; MS 184 (0.36) M+, 125 (3.60) M -C3H70, 97 (100) methylcyclohexyl, 88 (11.14)CH3CH2CH(OH)CHO; IR 3478,1698,1457,1403,1378.Anal.Calcd for CuH aA : C, 71.70; H, 10.94.Found: C, 71.59; H, 10.95.2-Hydroxy-l-( l-methylcyclohexyl)-2-phenylethanone: !H NMR b 7.35 (m, 5 H), 5.45 (m, 1 H), 4.45 (m, 1 H), 1.4 (m, 10 H), 0.9 (s, 3 H); MS 215 (0.2), 136 (2.6) PhCH(OH)CHO, 125 (13.1)CH3C6H10CO, 107 (33.4) PhCHOH, 97 (100) methylcyclohexyl, 77 (22.3)Ph.Anal.Calcd for C^HjA : C, 77.55; H, 8.68.Found: C, 77.43; H, 8.39.3-Hydroxy-4-dodecanone: *H NMR b 4.4 (m, 1 H), 4.2 (m, 1 H), 2.5 (m, 2 H), 1.7 (m, 2 H), 1.3 (m, 12 H), 0.95 (m, 6 H); MS 200 (0.89) M+, 141 (28.98)C8H17CO, 59 (100) CH3CH2CHOH; IR 3492, 1715, 1461, 1411.Anal.Calcd for C12H240 2: C, 71.95; H, 12.07, Found: C, 72.16; H, 11.89.l-(l-Hydroxycyclohexyl)-l-nonanone: *H NMR b 3.6 (m, 1 H), 2.55 (t, J = 8.1 Hz, 2 H), 1.67 (m, 10 H), 1.27 (m, 12 H), 0.88 (t, J = 6.2 Hz, 3 H); 13C NMR b 214.2, 77.2, 35.0, 33.1, 31.1, 28.7, 28.6, 28.4,24.6, 23.1, 21.9, 20.4,13.4;MS 241 (0.63) M+, 141 (0.45) C8H17CO, 99 (100) C6H10OH, 81 (30.79) cyclohexenyl.Anal.Calcd for C15H2s02: C, 74.95; H, 11.74.Found: C, 75.01;H, 11.48.l-(l-Hydroxycyclohexyl)ethanone: *H NMR b 3.6 (m, 1 H), 2.25 (s, 3 H), 1.6 (m, 10 H); MS 143 (0.16) M+, 99 (98) C6H10OH, 81 (100) cyclohexenyl.Anal.Calcd for C8H140 2: C, 67.57; H, 9.92.Found: C, 67.33; H, 9.96. Note Added in Proof:We recently found that benzoyl chloride gives 3 mainly when quenching is performed in anaerobic conditions.Benzil 2 has been therefore produced by very fast air oxidation of precursor ene diol prior to tautomerization to 3 (for a similar observation, see: Duhamel, L.; et al.
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Sijbesma et al. (1991) studied this question.