O-乙基-N,N'-二异丙基异脲

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: 7.5 g of ethyl N,N'-diisopropyl-carbamimidate were added to a solution of 7.8 g of (1R,cis) 2,2-dimethyl-3-cyclopentylidenemethyl-cyclopropane-1-carboxylic acid in 20 ml of ethyl acetate and the mixture was refluxed for 2 hours and was filtered. The filtrate was evaporated to dryness and the 13 g of residue were chromatographed over silica gel. Elution with a 7-3 cyclohexane-ethyl acetate mixture and the fraction with a Rf=0.45 was evaporated to dryness under reduced pressure to obtain 1.4 g of ethyl (1R,cis) 2,2-dimethyl-3-cyclopentylidenemethyl-cyclopropane-1-carboxylate with a specific rotation of [α]D20 =+76°±2° (c=1% in ethanol). the mixture was refluxed for 2 hours was filtered The filtrate was evaporated to dryness the 13 g of residue were chromatographed over silica gel Elution with a 7-3 cyclohexane-ethyl acetate mixture the fraction with a Rf=0.45 was evaporated to dryness under reduced pressure

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: Using the procedure of Example 17, 7.8 g of (1R,trans) 2,2-dimethyl-3-[(E) (dihydro-2-oxo-3(2H)-furanylidene)-methyl]-cyclopropane-1-carboxylic acid and 7 g of ethyl N,N'-diisopropylcarbamimidate were reacted to obtain 5 g of ethyl (1R,trans) 2,2-dimethyl-3-[(E) (dihydro-2-oxo-3-(2H)-furanylidene)-methyl]-cyclopropane-1-carboxylate with a specific rotation of [α]D20 =+50°±2° (c=0.5% in ethanol). were reacted