반응 #9011

반응 방정식

AlCl3

CH3SCN

BCl3

m-cresol

→

2-Hydroxy-4-methylbenzonitrile

수율 91.1%

용매

1,2-dichloroethane

반응 조건

후처리

1. 1
   기타2-Hydroxy-4-methylbenzonitrile was prepared
2. 2
   기타The cooling bath was removed
3. 3
   온도then cooled to room temperature
4. 4
   workup.ADDITIONThe mixture was poured into 4 N NaOH (35 mL)
5. 5
   온도the mixture was heated at 80° C. for 45 minutes
6. 6
   온도then cooled to room temperature
7. 7
   기타The phases were separated
8. 8
   추출the aqueous phase was extracted with CH2Cl2 (3×50 mL)
9. 9
   추출extracted with diethyl ether (3×50 mL)
10. 10
    건조The combined ether extracts were dried (MgSO4)
11. 11
    농축concentrated
12. 12
    기타Purification of the crude material by column chromatography on silica gel (20:1 CH2Cl2—EtOAc)

실험 절차

2-Hydroxy-4-methylbenzonitrile was prepared following a modification of the procedure reported by Makoto Adachi and Tsutomu Sugasawa (Synthetic Communications 1990, 20, 71–84.). To a cold (0° C.) solution of BCl3 (1.0 M in heptane, 12.0 mL, 12.0 mmol) in 1,2-dichloroethane was added neat m-cresol (1.00 mL, 9.56 mmol) followed by CH3SCN (0.83 mL, 12.1 mmol) and AlCl3 (1.38 g, 10.4 mmol). The cooling bath was removed and the resultant mixture was heated to 80° C. for 3 hours then cooled to room temperature. The mixture was poured into 4 N NaOH (35 mL) and the mixture was heated at 80° C. for 45 minutes then cooled to room temperature. The phases were separated and the aqueous phase was extracted with CH2Cl2 (3×50 mL). The aqueous phase was acidified with 6 N HCl (30 mL) and extracted with diethyl ether (3×50 mL). The combined ether extracts were dried (MgSO4) and concentrated. Purification of the crude material by column chromatography on silica gel (20:1 CH2Cl2—EtOAc) provided 1.16 g (91%) of 2-Hydroxy-4-methylbenzonitrile as a white solid. 1H NMR (CDCl3) δ 2.36 (s, 3H), 6.20 (br s, 1H), 6.79–6.81 (m, 2H), 7.38 (d, 1H, J=9 Hz).

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