Dimethyl Sulfoxide → HCID 19099323, compound

HRID 1975474Notes

Reaction equation

HRID 1975474 reaction equation
C(Cl)(=O)C(Cl)=O.CS(C)=O.[CH2:11]([O:18][C:19]([N:21]1[CH2:25][CH:24]([CH:26]([OH:28])[CH3:27])[CH2:23][N:22]1[C:29]([O:31][CH2:32][C:33]1[CH:38]=[CH:37][CH:36]=[CH:35][CH:34]=1)=[O:30])=[O:20])[C:12]1[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=1.C(N(CC)CC)C>ClCCl>[CH3:27][C:26]([CH:24]1[CH2:25][N:21]([C:19]([O:18][CH2:11][C:12]2[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=2)=[O:20])[N:22]([C:29]([O:31][CH2:32][C:33]2[CH:38]=[CH:37][CH:36]=[CH:35][CH:34]=2)=[O:30])[CH2:23]1)=[O:28]

Participants

6

Reactant 4

HCID 679Dimethyl SulfoxideHCID 8471TriethylamineHCID 65578Oxalyl chlorideHCID 19099247HCID 19099247, compound

Product 1

HCID 19099323HCID 19099323, compoundYield 9.2%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Conditions

Temperature
0 °C

Procedure

To a solution of oxalyl chloride (23 ml) in dichloromethane was added dropwise dimethyl sulfoxide (374 ml) while keeping the temperature below -50° C. After the mixture was stirred for 30 minutes at -50° C.~-60° C., 1.2-bis(benzyloxycarbonyl)-4-(1-hydroxyethyl)pyrazolidine (675 g) was added dropwise below -50° C. After the mixture was stirred for 45 minutes at -50° C.~-60° C., triethylamine (122 ml) was added dropwise below -50° C. The reaction mixture was allowed to warm to 0° C. and quenched with water (500 ml). The aqueous layer was separated and extracted twice with dichloromethane (200 ml×2). The combined organic layer was washed with 1N hydrochloric acid (200 ml×2), saturated sodium bicarbonte (200 ml), and 5% sodium chloride (200 ml), dried over magnesium sulfate, and evaporated under reduced pressure. The residue was chromatographed on silica gel (820 ml, hexane:ethyl acetate=2:1~1:1) to give 1,2-bis(benzyloxycarbonyl)pyrazolidin-4-yl methyl ketone (61.5 g).

Workup

  1. customthe temperature below -50° C
  2. stirringAfter the mixture was stirred for 45 minutes at -50° C.~-60° C.
  3. customquenched with water (500 ml)
  4. customThe aqueous layer was separated
  5. extractionextracted twice with dichloromethane (200 ml×2)
  6. washThe combined organic layer was washed with 1N hydrochloric acid (200 ml×2), saturated sodium bicarbonte (200 ml), and 5% sodium chloride (200 ml)
  7. dry with materialdried over magnesium sulfate
  8. customevaporated under reduced pressure
  9. customThe residue was chromatographed on silica gel (820 ml, hexane:ethyl acetate=2:1~1:1)

Sources & evidence

ORD record
ord-001b5da0991448ed86e080fad5263e4f
Source dataset
uspto-grants-1994_02
Patent number
US05286721

Reaction notes

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