Hydrochloric Acid → 2-Ethyl-2,3-dihydro-1lambda~6~-naphtho[2,1-e][1,2]thiazine-1,1,4-trione

HRID 1730577Notes

Reaction equation

HRID 1730577 reaction equation
C1O[C:4]2([C:9]3[CH:10]=[CH:11][C:12]4[C:17]([C:8]=3[S:7](=[O:19])(=[O:18])[N:6]([CH2:20][CH3:21])[CH2:5]2)=[CH:16][CH:15]=[CH:14][CH:13]=4)[O:3]C1.Cl>CO>[CH2:20]([N:6]1[CH2:5][C:4](=[O:3])[C:9]2[CH:10]=[CH:11][C:12]3[C:17]([C:8]=2[S:7]1(=[O:19])=[O:18])=[CH:16][CH:15]=[CH:14][CH:13]=3)[CH3:21]

Participants

4

Reactant 2

HCID 313Hydrochloric AcidHCID 86734204HCID 86734204, compound

Product 1

HCID 214980992-Ethyl-2,3-dihydro-1lambda~6~-naphtho[2,1-e][1,2]thiazine-1,1,4-trioneYield 84%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

A suspension of 10.9 gm (0.34 mol) of 2-ethyl-2H-naphtho[2,1-e]-1,2-thiazine-4(3H)-one-1,1-dioxide-ethylene ketal in 200 ml of methanol and 200 ml of aqueous 10% hydrochloric acid was refluxed for 1 hour. Then, the mixture was evaporated to dryness in vacuo, the residue was taken up in methylene chloride, and the solution was neutralized and again evaporated to dryness. Recrystallization of the residue from ethanol yielded 7.9 gm (84% of theory) of 2-ethyl-2H-naphtho[2,1-e]-1,2-thiazine-4(3H)-one-1,1-dioxide, m.p. 146°-147° C.

Workup

  1. temperaturewas refluxed for 1 hour
  2. customThen, the mixture was evaporated to dryness in vacuo
  3. customagain evaporated to dryness
  4. customRecrystallization of the residue from ethanol

Sources & evidence

ORD record
ord-52893badd121482598de44ca64f27f9e
Source dataset
uspto-grants-1976_11
Patent number
US03992535

Reaction notes

Loading…