Typical Procedure for Preparation of Products 4a–4d. Dimedone (0.140 g, 1 mmol) and aldehyde (1 mmol) were
dissolved in 1 mL DMSO and added to the fermenting yeast prepared under the above described condition. The reaction
mixture was shaken at 30ꢆC and 150 rpm for 24 h.
Purification and Structural Analysis of Products. The reaction mixture was extracted with chloroform (three
times). The organic layer was dried and concentrated under vacuum to give a crude product. The residue was purified by
preparative thin-layer chromatography on silica gel using n-hexane–ethyl acetate as the solvent.
2-Ethyl-2-hydroxy-5,5-dimethylcyclohexane-1,3-dione (2a). C H O . Colorless needle crystals, yield 0.123 g
10 16
3
+
–1
(88%), mp 90–93ꢆC. MS (m/z, %): 184 (M , 5%), 168 (44), 167 (22), 129 (40), 128 (34), 83 (100), 57 (56). IR (KBr, ꢇ, cm ):
3458, 2964, 2928, 1727, 1691. H NMR (300.13 MHz, CDCl , ꢄ, ppm, J/Hz): 3.82 (1H, br.s, OH), 2.89 (2H, d, J = 14, H-4, 6),
1
3
2.47 (2H, d, J = 14, H-4, 6), 1.97 (2H, q, J = 7.34, CH CH ), 1.24 (3H, s, CH ), 0.90 (3H, t, J = 7.34, CH CH ), 0.81 (3H, s,
2
3
3
2
3
13
CH ). C NMR (75.47 MHz, CDCl , ꢄ, ppm): 206.12 (C-1, 3), 89.42 (C-2), 50.89 (C-4, 6), 33.06 (CH CH ), 31.47 (C-5),
3
3
2
3
30.56 (CH ), 26.28 (CH ), 7.32 (CH CH ). X-Ray data: C H O , M = 184.23, monoclinic system, space group P2 /c;
3
3
2
3
10 16
3
1
ꢆꢃ
ꢆ 3
–3
a = 11.965 (2), b = 10.202 (2), c = 16.722 (3) A, ꢂ = 103.56 (3)ꢆ, V = 1984.3 (7) A ; Z = 8; D
= 1.233 g·cm ;
calc
–1
3
ꢈ (Mo–Kꢀ) = 0.090 mm ; T = 120 (2) K; crystal size 0.37 ꢅ 0.35 ꢅ 0.2 mm . The X-ray diffraction measurement was made
on a STOE IPDS-2T diffractometer with graphite monochromated Mo-Kꢀ radiation. The structure was solved using SHELXS.
The structure refinement and data reduction were carried out with SHELXL using the X-STEP32 suite of programs [21]. The
2
non-hydrogen atoms were refined anisotropically by full matrix least-squares on F values to final R = 0.0959, wR = 0.2261,
1
2
and S = 1.042 with 249 parameters using 3491 independent reflections. Hydrogen atoms attached to oxygen atoms were
located in a difference Fourier map and refined isotropically. All other hydrogen atoms were added in idealized positions. The
crystallographic information file has been deposited with the Cambridge Data Centre, CCDC 920547.
2-Ethyl-2-hydroxycyclohexane-1,3-dione (2b). C H O . Light yellow crystals, yield 0.14 g (90%), mp 158–162ꢆC.
8
12 3
+
–1
MS (m/z, %): 156 (M , 5%), 115 (29), 100 (39), 57 (100). IR (KBr, ꢇ, cm ): 3428, 2968, 2927, 2875, 1710, 1643, 1570.
H NMR (300.13 MHz, CDCl , ꢄ, ppm, J/Hz): 3.28 (1H, br.s, OH), 2.36 (4H, br.t, H-4, 6), 2.21 (2H, q, J = 7.34, CH CH ),
1
3
2
3
13
1.89 (2H, quintet, J = 6.34, H-5), 0.86 (3H, t, J = 7.34, CH CH ). C NMR (75.47 MHz, CDCl , ꢄ, ppm): 207.87 (C-1, 3),
2
3
3
91.00 (C-2), 32.34 (C-4, 6), 20.60 (CH CH ), 14.51 (C-5), 12.16 (CH CH ).
2
3
2
3
2-Ethyl-2-hydroxy-2H-indene-1,3-dione (2c). C H O . Yellow oil, yield 0.057 g (30%). MS (m/z, %): 190
11 10
3
+
–1
1
(M , 26%), 174 (6), 149 (30), 133 (47), 104 (63), 76 (81), 57 (100). IR (KBr, ꢇ, cm ): 3436, 2923, 2857, 1714, 1593. H NMR
(300.13 MHz, CDCl , ꢄ, ppm, J/Hz): 8.02 (2H, m, ArH). 7.93 (2H, m, ArH), 2.18 (br.s, OH), 1.93 (2H, q, J = 7.22, CH CH ),
3
2
3
13
0.94 (3H, t, J = 7.22, CH CH ). C NMR (75.47 MHz, CDCl , ꢄ, ppm): 199.79 (C-1, 3), 140.31 (C-4a, 7a), 136.37 (C-5, 6),
2
3
3
123.92 (C-4, 7), 79.4 (C-2), 29.70 (CH CH ), 7.66 (CH CH ).
2
3
2
3
5-Ethyl-5-hydroxy-2,2-dimethyl-1,3-dioxane-4,6-dione (2d). C H O . Colorless needle crystals, yield 0.169 g (90%),
8
12 5
+
–1
mp 107–108ꢆC. MS (m/z, %): 188 (M , 1%), 172 (11), 170 (5), 150 (15), 115 (22), 105 (100), 104 (10). IR (KBr, ꢇ, cm ):
3429, 2985, 2919, 2892, 1785, 1739, 1401, 1314. H NMR (300.13 MHz, CDCl , ꢄ, ppm, J/Hz): 3.52 (1H, t, J = 4.5, OH), 2.19
(2H, dq, J = 7, 4.5, CH CH ), 1.80 (3H, s, CH ), 1.78 (3H, s, CH ), 1.07 (3H, t, J = 7.2, CH CH ). C NMR (75.47 MHz,
1
3
13
2
3
3
3
2
3
CDCl , ꢄ, ppm): 165.5 (C-4, 6), 104.8 (C-5), 47.1 (C-2), 29.7 (CH CH ), 26.9 (CH ), 20.0 (CH ), 10.7 (CH CH ).
3
2
3
3
3
2
3
4-Chlorophenyl-2,2ꢁ-methylene-bis(3-hydroxy-5,5-dimethyl-2-cyclohexen-1-one) (4a). Yield 0.37 g (92%), mp
–1
1
139–142ꢆC; lit. mp [22] 139ꢆC. IR (KBr, ꢇ, cm ): 3427, 2958, 1590, 1489, 1376. H NMR (300.13 MHz, CDCl , ꢄ,
3
ppm, J/Hz): 11.89 (1H, br.s, OH), 10.09 (1H, br.s, OH), 7.25 (2H, d, J = 7.9, ArH), 7.03 (2H, d, J = 7.9, ArH), 5.49 (1H, s,
CH), 2.51–2.29 (8H, m, CH ), 1.23 (6H, s, CH ), 1.12 (6H, s, CH ).
2
3
3
4-Fluorophenyl-2,2ꢁ-methylene-bis(3-hydroxy-5,5-dimethyl-2-cyclohexen-1-one) (4b). Yield 0.33 g (85%),
–1
1
mp 183–185ꢆC; lit [23] mp 185–187ꢆC. IR (KBr, ꢇ, cm ): 3410, 2961, 2934, 1594, 1526. H NMR (300.13 MHz, CDCl ,
3
ꢄ, ppm, J/Hz): 11.90 (1H, br.s, OH), 11.56 (1H, br.s, OH), 6.93–7.07 (4H, m, ArH), 5.49 (1H, s, CH), 2.35–2.44 (8H, m, CH ),
2
1.27 (6H, s, CH ), 1.11 (6H, s, CH ).
3
3
Phenyl-2,2ꢁ-methylene-bis(3-hydroxy-5,5-dimethyl-2-cyclohexen-1-one) (4c). Yield 0.313 g (81%), mp 189–190ꢆC,
–1
1
lit. [22] mp 190–191ꢆC. IR (KBr, ꢇ, cm ): 3412, 2953, 2870, 1650, 1582. H NMR (300.13 MHz, CDCl , ꢄ, ppm, J/Hz);
3
11.65 (1H, br.s, OH), 9.98 (1H, br.s, OH), 6.54–6.83 (5H, m, ArH), 5.48 (1H, s, CH), 2.32–2.45 (8H, m, CH ), 1.18 (6H, s,
2
CH ), 1.09 (6H, s, CH ).
3
3
4-Nitrophenyl-2,2ꢁ-methylene-bis(3-hydroxy-5,5-dimethyl-2-cyclohexen-1-one) (4d). 0.363 g (88%),
–1
1
mp 188–190ꢆC, lit. [22] mp 189ꢆC. IR (KBr, ꢇ, cm ): 2950, 1591, 1510, 1376. H NMR (300.13 MHz, CDCl , ꢄ, ppm, J/Hz):
3
11.73 (2H, br.s, OH), 8.09 (2H, d, J = 7.7, ArH), 7.23 (2H, d, J = 7.7, ArH), 5.52 (1H, s, CH), 2.43 (8H, m, CH ), 1.19 (6H, s,
2
CH ), 1.11 (6H, s, CH ).
3
3
859