Triethylamine → 1-(Hydroxymethyl)-cyclopentanecarboxylic acid methyl ester

Temperatur

0 °C

To a solution of cyclopentane-1,1-dicarboxylic acid methyl ester (1.00 g, 5.81 mmol) and triethylamine (808 uL, 5.81 mmol) in THF (15 mL) is added isobutyl chloroformate (750 uL, 5.81 mmol) at 0° C. The mixture is stirred at 0° C. for 20 minutes. The mixture is filtrated, and the filtrate is added to a suspension of NaBH4 (242 mg) in THF (15 ml) at 0° C. The mixture is stirred at 0° C. for 3 hours and at room temperature for 12 hours. To the mixture, H2O is added and the mixture is extracted with AcOEt. The organic layer is dried over MgSO4, and concentrated under reduced pressure. The obtained residue is purified by silica gel column chromatography to give 1-hydroxymethyl-cyclopentanecarboxylic acid methyl ester (433 mg, 47%); TLC (hexane/AcOEt, 1:1) Rf 0.43, 1H NMR (400 MHz, chloroform-d) 8 ppm 1.61-1.77 (m, 6H), 1.93-2.00 (m, 2H), 2.53 (m, 1H), 3.57 (d, 2H), 3.72 (s, 3H).

1. filtrationThe mixture is filtrated
2. additionthe filtrate is added to a suspension of NaBH4 (242 mg) in THF (15 ml) at 0° C
3. stirringThe mixture is stirred at 0° C. for 3 hours and at room temperature for 12 hours
4. additionTo the mixture, H2O is added
5. extractionthe mixture is extracted with AcOEt
6. dry with materialThe organic layer is dried over MgSO4
7. concentrationconcentrated under reduced pressure
8. customThe obtained residue is purified by silica gel column chromatography

ORD-Eintrag

ord-c0875bd33e7046f29274cf790f763922

Quelldatensatz

uspto-grants-2013_05

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08440682B2