An Investigation of the Enolization and Isomeric Products Distribution in the Water Promoted Aldol Reaction of Tropinone and Granatanone
Table 1
Distributions of the products of the aldol reaction of tropinone and granatanone with benzaldehyde at 25°C calculated with different methods.
Method [lit. ref.]
Reaction medium
Tropinone (exp. neat 10 : 90, water 41 : 59)
Granatanone (exp. neat 11 : 89, water 39 : 61)
Calculated anti : syn
Deviation of calculated from experimental [%]
MAD
Calculated anti : syn
Deviation of calculated from experimental [%]
MAD
M062X/6-31g(d)
Gas/neat
3 : 97
72
70
5 : 95
57
46.5
Water
18 : 82
68
29 : 71
36
BH&HLYP/6-31g(d)
Gas/neat
11 : 89
11
20
10 : 90
10
9
Water
33 : 67
29
37 : 63
8
B3LYP/6-31G(d)
Gas/neat
11 : 89
11
5.5
11 : 89
0
2
Water
41 : 59
0
38 : 62
4
B3LYP/6-31G(d,p)
Gas/neat
10 : 90
0
9.5
9 : 91
20
18
Water
36 : 64
19
35 : 65
16
B3LYP/6-311++G(3d,3p)
Gas/neat
17 : 83
84
56
16 : 84
54
33
Water
47 : 53
28
36 : 64
12
BH&HLYP/cc-pVDZ
Gas/neat
11 : 89
11
17
9 : 91
20
12
Water
35 : 65
23
40 : 60
4
Diastereoisomer ratio of anti to syn isomers as indicated by NMR analysis. Diastereoisomer ratio given as a ratio of the sum of both anti forms (HB-O, HB-N) to both syn forms (HB-O, HB-N). Calculated as . MAD: mean average deviations to experimental results.