Water → HCID 86735074, compound

HRID 461430Notes

Reaction equation

HRID 461430 reaction equation
[O:1]1[CH:3]2[C:4]3[CH:13]=[CH:12][CH:11]=[CH:10][C:5]=3[O:6][C:7]([CH3:9])([CH3:8])[CH:2]12.[N-:14]=[N+:15]=[N-:16].[Na+].O>O1CCOCC1>[N:14]([C@H:3]1[C@H:2]([OH:1])[C:7]([CH3:9])([CH3:8])[O:6][C:5]2[CH:10]=[CH:11][CH:12]=[CH:13][C:4]1=2)=[N+:15]=[N-:16]

Participants

5

Reactant 3

HCID 962WaterHCID 33557Sodium AzideHCID 10910096HCID 10910096, compound

Product 1

HCID 86735074HCID 86735074, compound

Reagents, catalysts & solvents 1

HCID 312751,4-DioxaneSolvent

Procedure

3,4-Epoxy-3,4-dihydro-2,2-dimethyl-2H-benzo[b]pyran (3.00g.) and sodium azide (1.23g.; an excess) were refluxed in dioxane (25 ml.) and water (5 ml.) mixture for 24 hours. Dilution with water and extraction via diethyl ether gave trans-4-azido-3,4-dihydro-2,2-dimethyl-2H-benzo[b]-pyran-3-ol (3.06g.) as needles from 60°-80° petroleum ether m.p. 70° - 71°. To a solution of the hydroxy azide (2.90g.) in acetone (50 ml.) containing concentrated hydrochloric acid (10 ml.) was added with stirring and in portions, zinc dust (10 g.). Stirring was continued until gas evolution ceased. The zinc was filtered and washed with acetone. The combined washings and filtrate were diluted with water and extracted with diethyl ether. Basification of the aqueous layer and isolation via diethyl ether gave trans-4-amino-3,4-dihydro-2,2-dimethyl-2H-benzo[b]pyran-3-ol (2.70 g.), re-crystallised from ethanol m.p. 138°. Treatment with anhydrous hydrochloric acid as in Example 1 yielded trans-4-amino-3,4-dihydro-2,2-dimethyl-2H-benzo[b]pyran-3-ol hydrochloride, m.p. 223°-225°.

Workup

  1. extractionDilution with water and extraction via diethyl ether

Sources & evidence

ORD record
ord-61ae22db48a549e6922961a69d94acfd
Source dataset
uspto-grants-1977_12
Patent number
US04062870

Reaction notes

Loading…