Pyrrolidine → Methyl 6-(cyclopentylmethylene)-5-oxo-5,6,7,8-tetrahydronaphthalene-2-carboxylate

HRID 505702

Reaction equation

HRID 505702 reaction equation
[O:1]=[C:2]1[CH2:11][CH2:10][CH2:9][C:8]2[CH:7]=[C:6]([C:12]([O:14][CH3:15])=[O:13])[CH:5]=[CH:4][C:3]1=2.[CH:16]1([CH:21]=O)[CH2:20][CH2:19][CH2:18][CH2:17]1.N1CCCC1>CO>[CH:16]1([CH:21]=[C:11]2[CH2:10][CH2:9][C:8]3[CH:7]=[C:6]([C:12]([O:14][CH3:15])=[O:13])[CH:5]=[CH:4][C:3]=3[C:2]2=[O:1])[CH2:20][CH2:19][CH2:18][CH2:17]1

Participants

5

Reactant 3

HCID 31268PyrrolidineHCID 70106Cyclopentanecarbaldehyde2×HCID 15309116Methyl 5-oxo-5,6,7,8-tetrahydronaphthalene-2-carboxylate

Product 1

HCID 66722547Methyl 6-(cyclopentylmethylene)-5-oxo-5,6,7,8-tetrahydronaphthalene-2-carboxylateYield 60%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

To a solution of methyl 5-oxo-5,6,7,8-tetrahydronaphthalene-2-carboxylate (3.4 g, 16.7 mmol) in methanol (30 mL) was added cyclopentanecarboxaldehyde (3.3 g, 33.3 mmol) and pyrrolidine (2.78 mL, 33.3 mmol). The solution was stirred for twenty hours at ambient temperature. The reaction was recharged with 0.5 mL of cyclopentanecarboxaldehyde. The resulting precipitate was collected by vacuum filtration to provide methyl 6-(cyclopentylmethylene)-5-oxo-5,6,7,8-tetrahydronaphthalene-2-carboxylate as a solid (2.8 g, 60% yield). LC/MS on 4.6×50 mm C-18 column, tR=6.71 minutes (10 to 90% acetonitrile/water over 8 minutes at 2 mL/minute with detection 254 nm, at 50° C.); ES-MS m/z 285 (M+H); 1H NMR (400 MHz, DMSO-d6) δ ppm 1.24-1.39 (m, 2H), 1.52-1.74 (m, 4H), 1.76-1.89 (m, 2H), 2.77 (t, J=5.77 Hz, 2H), 2.79-2.90 (m, 1H), 2.97 (t, J=6.44 Hz, 2H), 3.85 (s, 3H), 6.71 (d, J=9.94 Hz, 1H), 7.88 (d, J=6.44 Hz, 1H), 7.91 (s, 1H), 7.98 (d, J=8.06 Hz, 1H).

Workup

  1. filtrationThe resulting precipitate was collected by vacuum filtration

Sources & evidence

ORD record
ord-7560562e95a546e2bb5c7b88fbafb78e
Source dataset
uspto-grants-2010_08
Patent number
US07781428B2

Linked notes

Loading…