Pivaloyl chloride → 1,2,3,4,-Tetrahydro-6-trimethylacetoxy-N-3-(2-thienyl)propionylisoquinoline
Reaction equation
[OH:1][C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][CH:11]=1)[CH2:8][N:7]([C:12](=[O:20])[CH2:13][CH2:14][C:15]1[S:16][CH:17]=[CH:18][CH:19]=1)[CH2:6][CH2:5]2.[CH3:21][C:22]([CH3:27])([CH3:26])[C:23](Cl)=[O:24]>FC(F)(F)C(O)=O>[CH3:21][C:22]([CH3:27])([CH3:26])[C:23]([O:1][C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][CH:11]=1)[CH2:8][N:7]([C:12](=[O:20])[CH2:13][CH2:14][C:15]1[S:16][CH:17]=[CH:18][CH:19]=1)[CH2:6][CH2:5]2)=[O:24]Participants
4
Procedure
To a solution of the product of Example 14 (2.83 g) in trifluoroacetic acid (30 mL) at 0° C. was added dropwise trimethylacetyl chloride (1.4 mL) and the reaction allowed to warm to room temperature. After 4 hours, the reaction was quenched with water and concentrated, the residue was dissolved in CH2Cl2, washed with brine, dried (MgSO4), filtered and concentrated. Chromatography of the residue on silica gel (elution with 50% ethyl acetate/hexanes) provided 3.8 g of desired product.