Vol. 72, 2007 Yan Zhou and Zixing Shan*. Chiral Diols. A New Class of Additives for Direct Aldol Reaction Catalyzed by L-Proline.
Page 9512. Entry numbers in Table 3 did not appear in numerical order. The corrected table is presented with an additional scheme to obtain 4. TABLE 3. Direct Aldol Reaction Assisted by (S)-BINOLa
entry 1 2 3 4 5 6 7 8 9 10 11 12 13 14
R 4-ClC6H4 4-BrC6H4 3-BrC6H4 2,6-Cl2C6H3 Ph 9-anthranyl i-Pr
additive
sub./cat./additive
product
configurationb
conversion (%)c
yield (%)d
ee (%)e
(S)-1 no (S)-1 no (S)-1 no (S)-1 no (S)-1 no (S)-1 no (S)-1 no
10:3:0.1 10:3:0 10:3:0.1 10:3:0 10:3:0.1 10:3:0 10:3:0.1 10:3:0 10:3:0.1 10:3:0 10:3:0.1 10:3:0 10:3:0.1 10:3:0
4a
R R R R R R R R R R Rf Rf R R
94 82 90 88 89 92 95 94 79 60 30 14 -
79 76 76 82 86 89 90 80 56 43 23 10 46 43
83 75 97 75 95 75 96 89 98 72 87 92 90 88
4b 4c 4d 4e 4f 4g
a The reaction was carried out in acetone/DMSO (3:1) at 0 °C for 48 h. b Assigned by comparison of the HPLC retention time of the product with reported data (ref 17b). c Based on the aldehyde recovery after column chromatography. d Isolated yield after column chromatography. e Determined by HPLC. f Assigned by analogy.
JO063319W 10.1021/jo063319w Published on Web 12/19/2006
686
J. Org. Chem. 2007, 72, 686
