Hydrochloric Acid → Pirbuterol hydrochloride

HRID 596457Notes

Reaction equation

HRID 596457 reaction equation
[ClH:1].C(O)(=O)/C=C\C(O)=O.C1(C2[O:21][C:20]3[CH:22]=[CH:23][C:24]([CH:26]([OH:33])[CH2:27][NH:28][C:29]([CH3:32])([CH3:31])[CH3:30])=[N:25][C:19]=3[CH2:18][O:17]2)C=CC=CC=1>CO>[ClH:1].[ClH:1].[OH:17][CH2:18][C:19]1[C:20]([OH:21])=[CH:22][CH:23]=[C:24]([CH:26]([OH:33])[CH2:27][NH:28][C:29]([CH3:31])([CH3:30])[CH3:32])[N:25]=1

Participants

4

Reactant 2

HCID 313Hydrochloric AcidHCID 681200874H-1,3-Dioxino[5,4-b]pyridine-6-methanol, α-[[(1,1-dimethylethyl)amino]methyl]-2-phenyl-, (2Z)-2-butenedioate (1:1) (salt)

Product 1

HCID 68658Pirbuterol hydrochloride

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

To a solution of methanol (11.3 l.)--hydrogen chloride gas (620 g., 17 moles) at 20° C. is added, with stirring, 2-phenyl-6-(1-hydroxy-2-t-butylaminoethyl)-4-H-pyrido-[3,2-d]-1,3-dioxin maleate (1880 g., 4.24 moles) over a five minute period. The resulting solution is then stirred for 2 hours at 20°-25° C. and is then concentrated under reduced pressure to a volume of about 3 liters. Acetone (16 liters) is added to the concentrate and the resulting precipitate granulated at 25° C. for a half-hour. The white crystalline solid is separated by filtration and washed with acetone (4 liters). Yield = quantitative. M.P. 183°-187° C. (dec.).

Workup

  1. stirringThe resulting solution is then stirred for 2 hours at 20°-25° C.
  2. concentrationis then concentrated under reduced pressure to a volume of about 3 liters
  3. additionAcetone (16 liters) is added to the
  4. concentrationconcentrate
  5. waitthe resulting precipitate granulated at 25° C. for a half-hour
  6. customThe white crystalline solid is separated by filtration
  7. washwashed with acetone (4 liters)
  8. customYield = quantitative

Sources & evidence

ORD record
ord-d53f1f6662604298a27a112f43273027
Source dataset
uspto-grants-1977_03
Patent number
US04011231

Reaction notes

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