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

HRID 1607376Notes

Reaction equation

HRID 1607376 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

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-0cfd09d1dbb944b09cc1ac5f14356a91
Source dataset
uspto-grants-1989_09
Patent number
US04864055

Reaction notes

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