2,4-Pentanediol → N-Acetyl-2-pyrroline

HRID 2211207Notes

Reaction equation

HRID 2211207 reaction equation
[C:1]([N:4]1[CH2:8][CH2:7][CH2:6][CH:5]1[O:9]C)(=[O:3])[CH3:2].CC(O)CC(O)C.CN1CCCC1=O>O.CCOC(C)=O>[C:1]([N:4]1[CH2:8][CH2:7][CH:6]=[CH:5]1)(=[O:3])[CH3:2].[C:1]([N:4]1[CH2:8][CH2:7][CH2:6][CH:5]1[OH:9])(=[O:3])[CH3:2]

Participants

7

Reactant 3

HCID 122622,4-PentanediolHCID 13387N-methyl-2-pyrrolidoneHCID 127112051-(2-Methoxypyrrolidin-1-yl)ethan-1-one

Product 2

HCID 10909522N-Acetyl-2-pyrrolineHCID 13113443N-acetyl-2-hydroxypyrrolidine

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 8857Ethyl AcetateSolvent

Procedure

One g of N-acetyl-2-methoxypyrrolidine (largely E plus lesser an amounts of B, C and D), 0.9 g of 2,4-pentandiol and 240 mg of N-methyl-2-pyrrolidone internal standard were heated at 50°-55° C. in 1 mL of H2O. A separate sample was heated in 1 mL of EtOAc. Results in both samples were similar: rapid initial formation of a small peak at 8.02 min (cyclic hemiamidal of the diol?), followed by growth of major product peaks at 8.35 and 8.73 min, the epimeric cyclic acetals. Small quantities of dehydrated product G (r.t.=4.75 min), and, in the aqueous sample, N-acetyl-2-hydroxypyrrolidine, F (before A at ~5.6 min) were also produced. One of the diols appeared to react faster and to a greater extent than the other. Measurements at 3-4 hr were close to the overnight values: ~87% conversion of A, 60-70% of B and essentially quantitative conversion of C and D.

Workup

  1. customResults in both samples
  2. customfollowed by growth of major product peaks at 8.35 and 8.73 min

Sources & evidence

ORD record
ord-c300767292504d38b1a4a8f453f40a4f
Source dataset
uspto-grants-1995_10
Patent number
US05463007

Reaction notes

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