Water → (2-Aminobenzo[d]thiazol-6-yl)methanol

HRID 892331Notes

Reaction equation

[NH2:1][C:2]1[S:3][C:4]2[CH:10]=[C:9]([C:11](OCC)=[O:12])[CH:8]=[CH:7][C:5]=2[N:6]=1.[H-].C([Al+]CC(C)C)C(C)C.O.[Cl-].[Na+]>C1COCC1>[NH2:1][C:2]1[S:3][C:4]2[CH:10]=[C:9]([CH2:11][OH:12])[CH:8]=[CH:7][C:5]=2[N:6]=1

Participants

Conditions

Temperature: -70 °C

Procedure

50 g (0.225 mol) of ethyl 2-aminobenzothiazole-6-carboxylate are suspended in 1,000 ml of THF, cooled to -70° C., and 562.5 ml (0.675 mol) of diisobutylaluminum hydride (DIBAL, 20% strength in toluene, 1.2 molar) are slowly added dropwise under nitrogen. The reaction solution is stirred at -70° C. to -40° C. overnight and then without cooling for a further 3 hours. Then it is cooled to -70° C., 61.5 ml of water are added dropwise (vigorous exothermic reaction), and the mixture is allowed to reach room temperature. 305 ml of saturated sodium chloride solution are added, and the mixture is stirred at 20° C. for 1 hour. Precipitated aluminum hydroxide is filtered off with suction and washed with THF, and the filtrate is evaporated to dryness (36 g). The residue is dissolved in boiling ethanol, some insolubles are filtered off, and the filtrate is evaporated to dryness.

Workup

temperaturewithout cooling for a further 3 hours
temperatureThen it is cooled to -70° C.
custom(vigorous exothermic reaction)
customto reach room temperature
stirringthe mixture is stirred at 20° C. for 1 hour
filtrationPrecipitated aluminum hydroxide is filtered off with suction
washwashed with THF
customthe filtrate is evaporated to dryness (36 g)
dissolutionThe residue is dissolved
filtrationsome insolubles are filtered off
customthe filtrate is evaporated to dryness

Sources & evidence

ORD record: ord-9f35582cc4e54df2bd94f744321c679e
Source dataset: uspto-grants-1992_06
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: USRE033948

Reaction notes

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