Trimethyl orthoformate → 2-(4-Bromophenyl)-5,5-dimethyl-1,3-dioxane

HRID 1534673Notes

Reaction equation

HRID 1534673 reaction equation
[CH3:1][C:2]([CH3:7])([CH2:5][OH:6])[CH2:3][OH:4].COC(OC)OC.[Br:15][C:16]1[CH:23]=[CH:22][C:19]([CH:20]=O)=[CH:18][CH:17]=1.C([O-])(O)=O.[Na+]>ClCCl.C1(C)C=CC(S(O)(=O)=O)=CC=1>[CH3:1][C:2]1([CH3:7])[CH2:5][O:6][CH:20]([C:19]2[CH:22]=[CH:23][C:16]([Br:15])=[CH:17][CH:18]=2)[O:4][CH2:3]1

Participants

7

Reactant 4

HCID 9005Trimethyl orthoformateHCID 31344Neopentyl glycolHCID 707414-BromobenzaldehydeHCID 516892Sodium Bicarbonate

Product 1

HCID 137145152-(4-Bromophenyl)-5,5-dimethyl-1,3-dioxaneYield 101.3%

Reagents, catalysts & solvents 2

HCID 6101p-Toluenesulfonic acidCatalystHCID 6344DichloromethaneSolvent

Procedure

After successive addition of 37.5 g of 2,2-dimethyl-propane-1,3-diol, 18,75 ml of ortho-formic acid trimethylester and 20 mg of p-toluene sulfonic acid, a solution of 25 g of 4-bromobenzaldehyde in 250 ml of dichloromethane is stirred for 24 hours at room temperature. To finish the compound it is poured into saturated, aqueous NaHCO3 solution and extracted with diethylether. Crystallization of the crude product from hexane yields 37.1 g of 4-(5,5-dimethyl-1-,3-dioxan-2-yl)-bromobenzene with a melting point of 62°-64° C.

Workup

  1. extractionextracted with diethylether
  2. customCrystallization of the crude product from hexane

Sources & evidence

ORD record
ord-ffe9b3e55f40450888798f816eb549e7
Source dataset
uspto-grants-1992_02
Patent number
US05089635

Reaction notes

Loading…