2,2-Dimethyl-1,3-dioxane-4,6-dione → tert-Butyl (3-(2,2-dimethyl-4,6-dioxo-1,3-dioxan-5-yl)-3-oxopropyl)carbamate

HRID 2066915Notes

Reaction equation

HRID 2066915 reaction equation
[C:1]([NH:8][CH2:9][CH2:10][C:11]([OH:13])=O)([O:3][C:4]([CH3:7])([CH3:6])[CH3:5])=[O:2].[CH3:14][C:15]1([CH3:23])[O:22][C:20](=[O:21])[CH2:19][C:17](=[O:18])[O:16]1.Cl.CN(C)CCCN=C=NCC>CN(C)C1C=CN=CC=1.ClCCl>[C:4]([O:3][C:1](=[O:2])[NH:8][CH2:9][CH2:10][C:11]([CH:19]1[C:20](=[O:21])[O:22][C:15]([CH3:23])([CH3:14])[O:16][C:17]1=[O:18])=[O:13])([CH3:5])([CH3:6])[CH3:7]

Participants

6

Reactant 3

HCID 162492,2-Dimethyl-1,3-dioxane-4,6-dioneHCID 76809N-((1,1-dimethylethoxy)carbonyl)-beta-alanineHCID 27239391,3-Propanediamine, N'-(ethylcarbonimidoyl)-N,N-dimethyl-, monohydrochloride

Product 1

HCID 68556020tert-Butyl (3-(2,2-dimethyl-4,6-dioxo-1,3-dioxan-5-yl)-3-oxopropyl)carbamate

Reagents, catalysts & solvents 2

HCID 142844-(Dimethylamino)pyridineCatalystHCID 6344DichloromethaneSolvent

Procedure

Boc-β-alanine (25 g, 132 mmol), Meldrum's acid (20.9 g, 145 mmol) and 4-dimethylaminopyridine (DMAP, 24.2 g, 198 mmol) were dissolved in 700 mL of dry dichloromethane (DCM) at 0° C. under nitrogen atmosphere. To this solution 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCI, 30.4 g, 158 mmol) was added. The resulting solution was allowed to reach room temperature and stirred overnight. The reaction mixture was washed (0.5 L×4) with 5% KHSO4 aqueous solution. The organic layer was dried over anh. Na2SO4, filtered and evaporated under vacuum, affording crude [3-(2,2-dimethyl-4,6-dioxo-[1,3]dioxan-5-yl)-3-oxo-propyl]-carbamic acid tert-butyl ester that was dissolved in 600 mL of ethylacetate and refluxed for 4 hours. The solvent was reduced to 150 mL under vacuum and the resulting solution was allowed to crystallize at 4° C. overnight. The solid was filtered and washed with cold ethyl acetate affording 18.4 g (65% yield) of the title compound.

Workup

  1. customto reach room temperature
  2. washThe reaction mixture was washed (0.5 L×4) with 5% KHSO4 aqueous solution
  3. dry with materialThe organic layer was dried over anh. Na2SO4
  4. filtrationfiltered
  5. customevaporated under vacuum

Sources & evidence

ORD record
ord-48837958b52c47d1b6061c4ef1c35c1e
Source dataset
uspto-grants-2012_10
Patent number
US08293762B2

Reaction notes

Loading…