Carbon Dioxide → HCID 68914665, compound

HRID 1958510Notes

Reaction equation

HRID 1958510 reaction equation
[C:1]([N:5]1[C:13]2[C:8](=[CH:9][CH:10]=[CH:11][CH:12]=2)[CH2:7][CH:6]1C(O)=O)(=O)[CH2:2][CH3:3].[C:17]([C:23]([O:25][CH3:26])=[O:24])#[C:18][C:19]([O:21][CH3:22])=[O:20].C(=O)=O>C(OC(=O)C)(=O)C>[CH3:22][O:21][C:19]([C:18]1[C:17]([C:23]([O:25][CH3:26])=[O:24])=[C:1]([CH2:2][CH3:3])[N:5]2[C:13]3[CH:12]=[CH:11][CH:10]=[CH:9][C:8]=3[CH2:7][C:6]=12)=[O:20]

Participants

5

Reactant 3

HCID 280Carbon DioxideHCID 12980Dimethyl acetylenedicarboxylateHCID 43196838HCID 43196838, compound

Product 1

HCID 68914665HCID 68914665, compound

Reagents, catalysts & solvents 1

HCID 7918Acetic AnhydrideSolvent

Conditions

Temperature
120 °C

Procedure

A mixture of 1-propionyl-2,3-dihydro-1H-indole-2-carboxylic acid (4.49 g, 20.5 mmol) and dimethyl acetylenedicarboxylate (5.68 g, 40 mmol) in acetic anhydride (40 mL) was stirred in a flask equipped with a reflux condenser and a gas bubbler to monitor carbon dioxide evolution during the reaction. The mixture was heated to 120° C. for 4 hours until no gas was eliminated. The dark solution was concentrated in vacuo to dryness and the solid residue was recrystallized from methanol to yield 3-ethyl-8H-3a-aza-cyclopenta[a]indene-1,2-dicarboxylic acid dimethyl ester, 4.61 g (75%): mp 86-88° C.; 1H NMR (DMSO-d6) δ 1.22 (3H, t, J=7.4 Hz, Me), 3.08 (2H, q, J=7.4 Hz, CH2), 3.75 and 3.76 (each 3H, s, 2×OMe), 4.07 (2H, s, CH2), 7.27-7.31 (1H, m, ArH), 7.43-7.47 (1H, m, ArH), 7.59-7.64 (2H, m, ArH). Anal. Calcd. for C17H17NO4: C, 68.21; H, 5.72; N, 4.68. Found: C, 68.22; H, 5.74; N, 4.65.

Workup

  1. customequipped with a reflux condenser
  2. customduring the reaction
  3. concentrationThe dark solution was concentrated in vacuo to dryness
  4. customthe solid residue was recrystallized from methanol

Sources & evidence

ORD record
ord-a56eb430a9054f5e86d5a665509e53e6
Source dataset
uspto-grants-2013_04
Patent number
US08410130B2

Reaction notes

Loading…