| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1346193 | Tetrahedron: Asymmetry | 2013 | 6 Pages |
A chemoenzymatic synthesis of an enantiopure 6-substituted 5,6-dihydro-2H-pyran-2-one using bromobenzene as a starting material is presented. This important structural motif is found in a large number of chiral lactones that present a wide range of biological activities. The key features of the preparation include enzymatic dioxygenation of bromobenzene using Escherichia coli JM109 (pDTG601), microwave-assisted acyloin cleavage, and tin mediated lactonization. The stereochemical assignment for the alcohol was confirmed by NMR analysis of Mosheŕs derivatives.
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(1R,2S,3R)-2,3-O-Isopropylidenecyclohex-4-ene-1,2,3-triolC9H14O3[α]D25=-158 (c 1.03, CH2Cl2)Absolute configuration: (1R,2S,3R)Source of chirality: cis-3-bromo-1,2-dihydrocatechol
(1R,2S,3R)-1-O-[Dimethyl(1,1,2-trimethylpropyl)silyl]-2,3-O-isopropylidenecyclohex-4-ene-1,2,3-triolC17H32O3Si[α]D25=-73.7 (c 1.03, CH2Cl2)Absolute configuration: (1R,2S,3R)Source of chirality: cis-3-bromo-1,2-dihydrocatechol
(1R,2S,3R)-1-[Dimethyl(1,1,2-trimethylpropyl)silyl]cyclohex-4-ene-1,2,3-triolC14H28O3Si[α]D25=-93.0 (c 0.69, CH2Cl2)Absolute configuration: (1R,2S,3R)Source of chirality: cis-3-bromo-1,2-dihydrocatechol
(5R,6S)-5-[dimethyl(1,1,2-trimethylpropyl)silyloxy]-6-hydroxycyclohex-2-ene-1-oneC14H26O3Si[α]D25+7.3 (c 0.41, CH2Cl2)Absolute configuration: (5R,6S)Source of chirality: cis-3-bromo-1,2-dihydrocatechol
(2Z,5R)-5-[Dimethyl(1,1,2-trimethylpropyl)silyloxy]-6-oxo-2-hexenoic acidC14H26O4Si[α]D25=+7.8 (c 0.61, CH2Cl2)Absolute configuration: (5R)Source of chirality: cis-3-bromo-1,2-dihydrocatechol
Methyl (2Z,5R)-5-[dimethyl(1,1,2-trimethylpropyl)silyloxy]-6-hydroxy-2-hexenoateC15H28O4Si[α]D25+5.5 (c 0.61, CH2Cl2)Absolute configuration: (5R)Source of chirality: cis-3-bromo-1,2-dihydrocatechol
Methyl (2Z,5R)-5-hydroxy-6-p-nitrobenzoyloxy-2-hexenoateC14H15NO7[α]D22=+41 (c 0.1, CH2Cl2)Absolute configuration: (5R)Source of chirality: cis-3-bromo-1,2-dihydrocatechol
(R)-6-[p-Nitrobenzoyloxymethyl]-5,6-dihydro-2H-pyran-2-oneC13H11NO7[α]D22=+62.9 (c 3.2, CH2Cl2)Absolute configuration: (R)Source of chirality: cis-3-bromo-1,2-dihydrocatechol
Methyl (2Z,5R)-5-[(R)-3,3,3-trifluoro-2-methoxy-2-phenylpropanoyloxy]-6-p-nitrobenzoyloxy-2-hexenoateC24H22FNO9[α]D24=-15.5 (c 0.8, CH2Cl2)Absolute configuration: (5R)Source of chirality: cis-3-bromo-1,2-dihydrocatechol
Methyl (2Z,5S)-5-[(S)-3,3,3-trifluoro-2-methoxy-2-phenylpropanoyloxy]-6-p-nitrobenzoyloxy-2-hexenoateC24H22FNO9[α]D24=+3.4 (c 0.8, CH2Cl2)Absolute configuration: (5R)Source of chirality: cis-3-bromo-1,2-dihydrocatechol
