A Novel One-Pot and One-Step Microwave-Assisted Cyclization-Methylation Reaction of Amino Alcohols and Acetylated Derivatives with Dimethyl Carbonate and TBAC
Table 2
Synthesis of 4-substituted-3-alkyl-1,3-oxazolidin-2-ones under modified conditions.
Entry
Starting material
Reaction conditions 130°C, 10 min 200 W
Product
Yield (%)a,b
1
DMC
Starting material + other unidentified products
—
2
DMC
Only starting material
—
3
DMC, TBAC (0.2 eq)
74
4
DMC, TBAC (0.2 eq)
69
5
DMC, DMF
—
6
DMC, DMF
68
7
DMC, DMF, TEA (1.5 eq)
—
8
DMC, DMF, TEA (1.5 eq)
Unidentified products
—
9
DMC, TEA (1.5 eq)
84
10
DMC, TBAC (0.2 eq)
>99
11
DMC, TEA (1.5 eq)
>99
Isolated yields based on the starting amino alcohol. bProducts characterized by 1H and 13C NMR.