Reaction #2487403

Reaction equation

Phenol

triethylamine

Cyclobut-1-enecarboxylic acid

oxalyl dichloride

cyclobut-1-enecarboxylic chloride

→

11

Yield 47.3%

Phenyl cyclobut-1-enecarboxylate

Yield 47.3%

Solvents

CH2Cl2

CH2Cl2

Conditions

Workup

1. 1
   TemperatureThe temperature of the solution was raised to room temperature
2. 2
   Otherto react for 1 h
3. 3
   OtherThe solvent was evaporated
4. 4
   workup.ADDITIONbefore being added to
5. 5
   workup.STIRRINGThe reaction mixture was stirred for 16 h at rt
6. 6
   OtherThe reaction was quenched with 1 N HCl
7. 7
   Extractionwas extracted with CH2Cl2 (30 ml)
8. 8
   WashThe CH2Cl2 solution was washed with 5% NaHCO3 (2×10 ml)
9. 9
   Dryingdried over Na2SO4
10. 10
    Concentrationconcentrated by rotary evaporation
11. 11
    Otherpurified by flash column chromatography (100% CH2Cl2)

Procedure

Cyclobut-1-enecarboxylic acid (0.51 mmol, 50 mg) was dissolved in 0.5 ml dry CH2Cl2. The solution was cooled to 0° C. and oxalyl dichloride (0.51 mmol, 43 μl) was added. The temperature of the solution was raised to room temperature, and the mixture was allowed to react for 1 h. The solvent was evaporated to generate a viscous oil. Phenol (0.51 mmol, 48 mg) and triethylamine (1.02 mmol, 142 μl) were dissolved in 0.5 ml dry CH2Cl2, and the solution was stirred at 0° C. for 45 min before being added to a vial containing the cyclobut-1-enecarboxylic chloride. The reaction mixture was stirred for 16 h at rt. The reaction was quenched with 1 N HCl, and was extracted with CH2Cl2 (30 ml). The CH2Cl2 solution was washed with 5% NaHCO3 (2×10 ml), dried over Na2SO4, concentrated by rotary evaporation, and then purified by flash column chromatography (100% CH2Cl2) to yield 11 as a colorless oil (42 mg, 47%). 1H-NMR (100 MHz) δ 7.42 (m, 2H), 7.28 (m, 1H), 7.14 (m, 2H), 7.02 (s, 1H), 2.88 (t, J=3.0 Hz, 2H), 2.60 (m, 2H). 13C-NMR (400 MHz) δ 160.5, 150.8, 149.2, 138.3, 129.6, 125.9, 121.8, 29.5, 27.7. HRMS (EI) calcd. for C11H10O2 [M]+ 174.0679, found 174.0681.

Source