Pyridine → Pyrane-4-carboxylic acid methylester
Reaction equation
COC([C:5]1[C@H]2C[C@@H]3O[C@@]3(CO)[C@@H:7]2[C@H:8](OC(=O)NC)[O:9][CH:10]=1)=O.N1C=CC=CC=1.[C:28]([O:31][C:32](=[O:34])[CH3:33])(=O)C>ClCCl.CN(C1C=CN=CC=1)C>[CH3:28][O:31][C:32]([C:33]1[CH:7]=[CH:8][O:9][CH2:10][CH:5]=1)=[O:34]Participants
Reactant 3
Product 1
Reagents, catalysts & solvents 2
Procedure
500 mg of the (1S,4aS,6S,7R,7aR)-6,7-epoxy-7-(hydroxymethyl)-1-(methylcarbamoyloxy)-1,4a,5,6,7,7a-hexahydrocyclopenta [c] pyrane-4-carboxylic acid methylester were dissolved in dichloromethane followed by addition of 0.4 ml of pyridine and 50 mg of DMAP. Next, 0.32 ml of acetic anhydride were dropped in followed by stirring for 4 hours at room temperature. The reaction mixture was then extracted with ethyl acetate. After washing the organic phase with 2N aqueous hydrochloric acid, saturated aqueous sodium bicarbonate and brine, it was dried over magnesium sulfate. After distilling off the solvent under reduced pressure, the residue was purified by silica gel chromatography to obtain a colorless foamy substance from the hexane-ether eluate in the form of (1S,4aS,6S.7R,7aR)-7-(acetoxymethyl)-6,7-epoxy-1-(methylcarbamoyloxy)-1,4a,5,6,7,7a-hexahydro [c] pyrane-4-carboxylic acid methylester (465 mg, yield: 82%). The physicochemical properties of this compound are described in Table 10, Compound No. 46.
Workup
- extractionThe reaction mixture was then extracted with ethyl acetate
- washAfter washing the organic phase with 2N aqueous hydrochloric acid, saturated aqueous sodium bicarbonate and brine, it
- dry with materialwas dried over magnesium sulfate
- distillationAfter distilling off the solvent under reduced pressure
- customthe residue was purified by silica gel chromatography
Sources & evidence
- ORD record
- ord-2da75003b1464e04bafc06e510834bae
- Source dataset
- uspto-grants-2001_05
- Patent number
- US06225478B1
Reaction notes
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