Lithium diisopropylamide mono(tetrahydrofuran) → HCID 53886547, compound
Reaction equation
O1CCC[CH2:2]1.[CH:6]([N-:9][CH:10](C)C)(C)C.[Li+].[C:14]([C:16]([C:30]#[N:31])=[C:17]1[CH2:21][CH2:20][N:19]([C:22]2[CH:27]=[CH:26][C:25]([O:28][CH3:29])=[CH:24][CH:23]=2)[CH2:18]1)#[N:15]>>[C:14]([C:16]([C:30]#[N:31])=[C:17]1[C:21](=[CH:6][N:9]([CH3:10])[CH3:2])[CH2:20][N:19]([C:22]2[CH:27]=[CH:26][C:25]([O:28][CH3:29])=[CH:24][CH:23]=2)[CH2:18]1)#[N:15]Participants
Procedure
Lithium diisopropylamide mono(tetrahydrofuran) (7.1 mL, 10.5 mmol, in 1.5M in cyclohexanol) is added dropwise to a suspension of 3-dicyanomethylene-1-(4-methoxyphenyl)pyrrolidine (2.10 g, 8.8 mmol) in 150 mL of freshly distilled (over calcium hydride) tetrahydrofuran in a dry ice-acetone bath. After stirring for 1 hour, dimethylaminomethylene chloride (prepared from 1.64 mL of phosphorus oxychloride and 1.36 mL of N,N-dimethylformamide in 10 mL of tetrahydrofuran) is added dropwise, and the stirring is continued at -65° C. for 18 hours. The solid is collected by filtration and triturated with 50 mL of boiling ethanol to give 3-dicyanomethylene-4-(N,N-dimethylamino)methylene-1(4-methoxyphenyl)pyrrolidine (1.02 g, 40%), mp 218°-219° C. (decomposition), IR (KBr) 2210 cm-1 (CN), 1H NMR (Me2SO-d6) d 3.31 (6H, s, NMe2), 3.68 (3H, s, OMe), 4.23 (2H, brs, CH2), 4.44 (2H, brs, CH2), 6.60 and 6.85 (each 2H, d, Ph), 8.24 (1H, s, NCH=).
Workup
- distillationof freshly distilled (over calcium hydride) tetrahydrofuran in a dry ice-acetone bath
- additiondimethylaminomethylene chloride (prepared from 1.64 mL of phosphorus oxychloride and 1.36 mL of N,N-dimethylformamide in 10 mL of tetrahydrofuran) is added dropwise
- waitthe stirring is continued at -65° C. for 18 hours
- filtrationThe solid is collected by filtration
- customtriturated with 50 mL of boiling ethanol
Sources & evidence
- ORD record
- ord-68b6eda51c8a404c946d69b8df627780
- Source dataset
- uspto-grants-1990_05
- Patent number
- US04925939
Reaction notes
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