Benzoic Acid → 2-Methyl-4-[(1R)-2,2,3-trimethylcyclopent-3-en-1-yl]but-2-en-1-ol
Reaction equation
[CH3:1][C:2](=[CH:5][CH2:6][C@H:7]1[CH2:11][CH:10]=[C:9]([CH3:12])[C:8]1([CH3:14])[CH3:13])[CH:3]=[O:4].C(O)(=O)C1C=CC=CC=1>>[CH3:1][C:2](=[CH:5][CH2:6][C@H:7]1[CH2:11][CH:10]=[C:9]([CH3:12])[C:8]1([CH3:14])[CH3:13])[CH2:3][OH:4]Participants
Conditions
- Temperature
- 100 °C
Procedure
(R)-2-methyl-4-(2,2,3-trimethylcyclopent-3-en-1-yl)but-2-enal (as a 98/2 E/Z isomers mixture) (384 g, 2 mol.), benzoic acid (2.44 g, 0.02 mol., 1 mol.%) and (ethylenediamine)[9,9-dimethyl-4,5-bis(diphenylphosphino)xanthene]ruthenium(bispivalate) (37.6 mg, 0.04 mmol, 0.002 mol.%) were loaded altogether in a 1 L autoclave equipped with a mechanical stirring device. Sealed autoclave was then purged under stirring with nitrogen (3 times 5 bars) and hydrogen (3 times 5 bars) before being pressurized to 50 bars hydrogen. It was then heated to 100° C. and hydrogen pressure was maintained to 50 bars during all the reaction to afford desired product with 97.5% selectivity as a 98/2 E/Z isomers mixture and no loss of optical purity. Upon complete reaction conversion (checked by both hydrogen consumption and GC), autoclave was cooled down to 25° C. It was then depressurized and purged with nitrogen (3 times 5 bars). After flash distillation, (R)-2-methyl-4-(2,2,3-trimethylcyclopent-3-en-1-yl)but-2-en-1-ol was obtained in 96.5% yield.
Workup
- customequipped with a mechanical stirring device
- customSealed autoclave
- customwas then purged
- temperaturehydrogen pressure was maintained to 50 bars during all
- customthe reaction
Sources & evidence
- ORD record
- ord-30a25160121942cebce9df42fbb19fde
- Source dataset
- uspto-grants-2015_07
- Patent number
- US09090534B2
Reaction notes
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