Pyridine → HCID 20200643, compound

HRID 979553Notes

Reaction equation

HRID 979553 reaction equation
O[C:2]([CH:6]1[NH:10][C:9](=[O:11])[CH2:8][CH2:7]1)([CH3:5])[C:3]#[CH:4].N1C=CC=CC=1.S(Cl)([Cl:20])=O>C1(C)C=CC=CC=1>[CH3:5][C:2]([CH:6]1[NH:10][C:9](=[O:11])[CH2:8][CH2:7]1)=[C:3]=[CH:4][Cl:20].[CH2:5]=[C:2]([CH:6]1[NH:10][C:9](=[O:11])[CH2:8][CH2:7]1)[C:3]#[CH:4]

Participants

6

Reactant 3

HCID 1049PyridineHCID 24386Thionyl ChlorideHCID 20200659HCID 20200659, compound

Product 2

HCID 20200643HCID 20200643, compoundHCID 20200652HCID 20200652, compound

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Procedure

To a toluene solution of 5-(1-hydroxy-1-methylprop-2-yn-1-yl)-2-pyrrolidone at room temperature was added 4.0 equivalents of pyridine and 1.5 equivalents of thionyl chloride. The reaction mixture was left for four days. It was then quenched with cold water, extracted repeatedly with ethyl acetate and the organic extract washed once with water, brine, dried over anh. MgSO4 and concentrated to give an oil. Purification by chromatography over silica gel gave a 1:1 ratio of 5-(1-methyl-3-chloro-1,2-propadien-1-yl)-2-pyrrolidone (IR 1960 cm-1) and 5-(1-methyleneprop-2-yne-1-yl)-2-pyrrolidone (IR 2100 cm-1). The mixture was then refluxed in a 1:1 solution of THF: 20% HCl for 2 days, diluted with water, and washed with ether. The aqueous phase was passed through an ion-exchange column (Ag 50 W×8) eluting with 20% pyridine-water. The concentrate was then chromatographed on HPLC (RP-18) giving two diasteromeric allenes which separated under the HPLC conditions. 4-Amino-5-methyl-7-chloro-5,6-heptadienoic acid; IR (KBr): 1962, 1545 cm-1, 'H NMR (δD2O): 1.93 (d, 3H, J=2.2 Hz, CH3), 1.9-2.5 (m, 4H, CH2CH2), 3.9 (m, 1H, CHN), 6.49 (m, 1H, CH=C), mass spectrum (M+Cl 154), 102, 84; and 4-amino-5-methylene-6-heptynoic acid IR: 3165, 2130, 1610, 1540 cm-1 ; 'H NMR (δD2O): 1.9-2.5 (m-4H, CH2CH2), 2.58 (s, 1H, C=CH), 2.96 (m, 1H, HCN), 5.8 (d, 2H, J=7.3 Hz, H2C=C).

Workup

  1. customIt was then quenched with cold water
  2. extractionextracted repeatedly with ethyl acetate
  3. extractionthe organic extract
  4. washwashed once with water, brine
  5. dry with materialdried over anh. MgSO4
  6. concentrationconcentrated
  7. customto give an oil
  8. customPurification by chromatography over silica gel

Sources & evidence

ORD record
ord-4185b36dd4a248c9be6d558b4a634acc
Source dataset
uspto-grants-1987_05
Patent number
US04668703

Reaction notes

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