Dicyclohexylcarbodiimide → tert.-butyl(1R,cis)2,2-dimethyl-3-[Z-2-(cyclobutoxycarbonyl)-ethenyl]cyclopropane-carboxylate
Reaction equation
[CH:1]1([OH:5])[CH2:4][CH2:3][CH2:2]1.[CH3:6][C:7]1([CH3:22])[C@@H:9](/[CH:10]=[CH:11]\[C:12](O)=[O:13])[C@H:8]1[C:15]([O:17][C:18]([CH3:21])([CH3:20])[CH3:19])=[O:16].C1(N=C=NC2CCCCC2)CCCCC1>C(Cl)Cl.CN(C)C1C=CN=CC=1>[CH3:6][C:7]1([CH3:22])[C@@H:9](/[CH:10]=[CH:11]\[C:12]([O:5][CH:1]2[CH2:4][CH2:3][CH2:2]2)=[O:13])[C@H:8]1[C:15]([O:17][C:18]([CH3:21])([CH3:20])[CH3:19])=[O:16]Participants
6
Reactant 3
Product 1
Reagents, catalysts & solvents 2
Procedure
1.7 ml of cyclobutanol were added to a solution of 4 g of tert.-butyl(1R,cis)2,2-dimethyl-3-[Z-2-carboxyethenyl]-cyclopropane-carboxylate in 20 ml of methylene chloride and 3.45 g of dicyclohexylcarbodiimide and a solution of 28 mg of 4-dimethylamino-pyridine in 20 ml of methylene chloride were added thereto at 0° to 5° C. with stirring. The mixture was stirred for 2 hours at 5° C. and 2 hours at room temperature and was then filtered. The filtrate was evaporated to dryness under reduced pressure and the residue was chromatographed over silica gel. Elution with a 9-1 n-hexane-isopropyl ether mixture yielded 2.3 g of tert.-butyl(1R,cis)2,2-dimethyl-3-[Z-2-(cyclobutoxycarbonyl)-ethenyl]cyclopropane-carboxylate.
Workup
- stirringThe mixture was stirred for 2 hours at 5° C. and 2 hours at room temperature
- filtrationwas then filtered
- customThe filtrate was evaporated to dryness under reduced pressure
- customthe residue was chromatographed over silica gel
- washElution with a 9-1 n-hexane-isopropyl ether mixture
Sources & evidence
- ORD record
- ord-ef2e80e18fe4427384e2adfeb6d592aa
- Source dataset
- uspto-grants-1985_10
- Patent number
- US04547522
Reaction notes
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