(+)-Methyl lactate → HCID 10636610, compound

HRID 1699351Notes

Reaction equation

HRID 1699351 reaction equation
Cl.C(N=C=NCCCN(C)C)C.[CH3:13][O:14][C:15]1[C:29]([O:30][CH3:31])=[CH:28][C:18]2[CH2:19][CH:20]([C:25]([OH:27])=[O:26])[S:21][CH2:22][C:23](=[O:24])[C:17]=2[CH:16]=1.C(OC)(=O)[C@@H](C)O>ClCCl.CN(C)C=O.CN(C)C1C=CN=CC=1>[CH3:13][O:14][C:15]1[C:29]([O:30][CH3:31])=[CH:28][C:18]2[CH2:19][C@H:20]([C:25]([OH:27])=[O:26])[S:21][CH2:22][C:23](=[O:24])[C:17]=2[CH:16]=1

Participants

7

Reactant 3

HCID 637514(+)-Methyl lactateHCID 27239391,3-Propanediamine, N'-(ethylcarbonimidoyl)-N,N-dimethyl-, monohydrochlorideHCID 18008856HCID 18008856, compound

Product 1

HCID 10636610HCID 10636610, compoundYield 36.7%

Reagents, catalysts & solvents 3

HCID 142844-(Dimethylamino)pyridineCatalystHCID 6228DimethylformamideSolventHCID 6344DichloromethaneSolvent

Conditions

Temperature
0 °C

Procedure

A solution of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (4.89 g) in dichloromethane (80 ml) was added to a solution of (±)-1,2,4,5-tetrahydro-7,8-dimethoxy-5-oxo-3-benzothiepin-2-carboxylic acid (6.0 g) and methyl (R)-(+)-lactate (4.43 g) in N,N-dimethylformamide (DMF) (80 ml) at 0° C., followed by the addition of 4-dimethylaminopyridine (DMAP) (1.3 g). This mixture was stirred at 0° C. for 1 hour and at room temperature for 15 hours, and concentrated under reduced pressure. Ethyl acetate (500 ml) and water (500 ml) were added to the residue and then the organic layer was collected. The organic layer was washed with water and dried (MgSO4), after which the solvent was distilled off; the residual solid was collected by filtration and washed with ether, followed by recrystallization twice from ethyl acetate-hexane to yield (R)-1-methoxycarbonylethyl ester of (2R)-(−)-1,2,4,5-tetrahydro-7,8-dimethoxy-5-oxo-3-benzothiepin-2-carboxylic acid (2.2 g, 28%). Colorless needles. Melting point 161-162° C. Optical rotation [α]D (16° C.) −194.1° (c=0.50, CHCl3). A filtrate of the above-mentioned solid was concentrated and the resulting crystals were collected by filtration with ether-hexane, followed by recrystallization twice from ethyl acetate-hexane to yield (R)-1-methoxycarbonylethyl ester of (2S)-(+)-1,2,4,5-tetrahydro-7,8-dimethoxy-5-oxo-3-benzothiepin-2-carboxylic acid (1.6 g, 20%). Colorless Plates. Melting point 121-122° C. Optical rotation [α]D (16° C.) +234.3° (c=0.50, CHCl3).

Workup

  1. concentrationconcentrated under reduced pressure
  2. additionEthyl acetate (500 ml) and water (500 ml) were added to the residue
  3. customthe organic layer was collected
  4. washThe organic layer was washed with water
  5. dry with materialdried (MgSO4)
  6. distillationafter which the solvent was distilled off
  7. filtrationthe residual solid was collected by filtration
  8. washwashed with ether
  9. customfollowed by recrystallization twice from ethyl acetate-hexane

Sources & evidence

ORD record
ord-b8fd23279f2a47ea9a74f495a5c039aa
Source dataset
uspto-grants-2002_02
Patent number
US06346521B1

Reaction notes

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