Acetic Anhydride → Acetate

HRID 1757372Notes

Reaction equation

HRID 1757372 reaction equation
[OH:1][C:2]1[CH:11]=[C:10]([CH3:12])[CH:9]=[CH:8][C:3]=1[S:4]([O-:7])(=[O:6])=[O:5].[CH3:13][C:14]([O:16]C(C)=O)=[O:15].CCN(CC)CC>C(Cl)Cl>[C:14]([O:1][C:2]1[CH:11]=[C:10]([CH3:12])[CH:9]=[CH:8][C:3]=1[S:4]([O-:7])(=[O:5])=[O:6])(=[O:15])[CH3:13].[C:14]([O-:16])(=[O:15])[CH3:13]

Participants

6

Reactant 3

HCID 7918Acetic AnhydrideHCID 8471TriethylamineHCID 18616153HCID 18616153, compound

Product 2

HCID 175AcetateHCID 19387706HCID 19387706, compound

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

The racemic acetate substrate was prepared by one of two methods. The diol route began with racemic 1,2-dihydroxy-3-butene which could be prepared by reacting EpB with water under neutral conditions or with acid catalysis. The diol was treated with p-toluenesulfonyl chloride (p-TsCl) in pyridine at 4° C. to afford the desired monotosylate contaminated with about 10% of the corresponding ditosylate. The monotosylate could be selectively crystallized to afford pure monotosylate in 61% yield. Hydroxy-tosylate was acetylated under normal conditions (Ac2O, Et3N, CH2Cl2) to provide the acetoxy-tosylate (the desired racemic acetate) in 93% yield. The diol route is illustrated as follows: ##STR3##

Sources & evidence

ORD record
ord-55829ee7e8654c6d85c4cb0b01708a53
Source dataset
uspto-grants-1995_08
Patent number
US05445963

Reaction notes

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