Reaction #1755470

Reaction equation

88

4-prop-2-ynyl-cyclohexanecarboxylic acid

CH2Cl2

MeOH

TMS Diazomethane

→

89

Yield 80.0%

Methyl 4-prop-2-ynylcyclohexanecarboxylate

Yield 80.0%

Solvents

acetic acid

Conditions

Workup

1. 1
   workup.STIRRINGAfter stirring
2. 2
   ConcentrationThe reaction was concentrated in vacuo to an oil which
3. 3
   Otherwas purified by flash chromatography on silica gel

Procedure

To a solution of 88 (240 mg, 1.45 mmol) in 7:3 CH2Cl2:MeOH (10 mL) was added TMS Diazomethane (2.0 M in hexanes) (0.9 mL, 1.8 mmol) in 0.2 ml aliquots until the color remained yellow. The reaction was allowed to stir for an additional 0.25 hours at room temperature. After stirring, glacial acetic acid was added dropwise until the solution became colorless. The reaction was concentrated in vacuo to an oil which was purified by flash chromatography on silica gel using ether:petroleum ether (1:9) to yield 89 (210 mg, 80%) as a clear oil. 1H NMR (CDCl3) δ 3.60 (s, 3H), 2.25-2.13 (m, 1H), 2.08-1.94 (m, 3H), 1.95-1.90 (m, 2H), 1.49-1.31 (m, 3H), 1.10-0.93 (m, 2H); 13C NMR (CDCl3) δ 176.7, 83.3, 69.8, 51.9, 43.4, 36.7, 31.9, 29.2, 26.3; APCI m/z (rel intensity) 181 (MH+, 100).

Source