1-Chloro-(2-methylpropyl) (methylethoxy)formate → 2-Methyl-1-(methylethoxycarbonyloxy)propyl (2R)-4-[(3-chloropropyl)sulfonyloxy]-3,3-dimethyl-2-(1,1,2,2-tetramethyl-1-silapropoxy)butanoate

HRID 1919452Notes

Reaction equation

HRID 1919452 reaction equation
[Cl:1][CH2:2][CH2:3][CH2:4][S:5]([O:8][CH2:9][C:10]([CH3:24])([CH3:23])[C@@H:11]([O:15][Si:16]([CH3:22])([CH3:21])[C:17]([CH3:20])([CH3:19])[CH3:18])[C:12]([OH:14])=[O:13])(=[O:7])=[O:6].[CH3:25][CH:26]([O:28][C:29]([O:31][CH:32](Cl)[CH:33]([CH3:35])[CH3:34])=[O:30])[CH3:27]>C1(C)C=CC=CC=1.C(=O)([O-])[O-].[Ag+2]>[Cl:1][CH2:2][CH2:3][CH2:4][S:5]([O:8][CH2:9][C:10]([CH3:24])([CH3:23])[C@@H:11]([O:15][Si:16]([CH3:22])([CH3:21])[C:17]([CH3:19])([CH3:18])[CH3:20])[C:12]([O:14][CH:32]([O:31][C:29]([O:28][CH:26]([CH3:27])[CH3:25])=[O:30])[CH:33]([CH3:35])[CH3:34])=[O:13])(=[O:7])=[O:6]

Participants

5

Reactant 2

HCID 861475011-Chloro-(2-methylpropyl) (methylethoxy)formateHCID 86628876(2R)-4-[(3-Chloropropyl)sulfonyloxy]-3,3-dimethyl-2-(1,1,2,2-tetramethyl-1-silapropoxy)butanoic acid

Product 1

HCID 866289212-Methyl-1-(methylethoxycarbonyloxy)propyl (2R)-4-[(3-chloropropyl)sulfonyloxy]-3,3-dimethyl-2-(1,1,2,2-tetramethyl-1-silapropoxy)butanoateYield 66.6%

Reagents, catalysts & solvents 2

HCID 178418647HCID 178418647, compoundCatalystHCID 1140TolueneSolvent

Procedure

Following the general procedure for the preparation of acyloxyalkyl/alkoxycarbonyloxyalkyl carboxylic esters from carboxylic acids of Description 22, (2R)-4-[(3-chloropropyl)sulfonyloxy]-3,3-dimethyl-2-(1,1,2,2-tetramethyl-1-silapropoxy)butanoic acid (15) (0.4 g, 0.99 mmol) dissolved in 5 mL of anhydrous toluene was reacted with 0.57 g (3.0 mmol) of 1-chloro-(2-methylpropyl) (methylethoxy)formate in the presence of 0.33 g (1.1 mmol) of silver carbonate (Ag2CO3). After work-up, the crude material was purified by silica gel column chromatography using a mixture of ethyl acetate (EtOAc) and hexane (Hxn) (EtOAc/Hxn=1:2) as eluent to provide 0.37 g of a mixture of the title compound (47a) and (3R)-4,4-dimethyl-3-(1,1,2,2-tetramethyl-1-silapropoxy)-3,4,5-trihydrofuran-2-one (4a). MS (ESI) m/z 583.12 (M+Na)+.

Workup

  1. customAfter work-up, the crude material was purified by silica gel column chromatography
  2. additiona mixture of ethyl acetate (EtOAc) and hexane (Hxn) (EtOAc/Hxn=1:2) as eluent

Sources & evidence

ORD record
ord-8917220340014a098f8ba26166e7af73
Source dataset
uspto-grants-2012_05
Patent number
US08168617B2

Reaction notes

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