Methanol → 2-Chloro-4-iodo-6-methoxy-5-(methoxymethyl)pyridine

HRID 373303Notes

Reaction equation

HRID 373303 reaction equation
[Cl:1][C:2]1[N:7]=[C:6]([O:8][CH3:9])[C:5]([CH:10]=[O:11])=[C:4]([I:12])[CH:3]=1.[CH2:13]([SiH](CC)CC)C.CO.FC(F)(F)C(O)=O.C([O-])(O)=O.[Na+]>CCOCC>[Cl:1][C:2]1[CH:3]=[C:4]([I:12])[C:5]([CH2:10][O:11][CH3:13])=[C:6]([O:8][CH3:9])[N:7]=1

Participants

7

Procedure

To a mixture of 6-chloro-4-iodo-2-methoxy-3-pyridinecarboxaldehyde (1.07 g, 3.60 mmol), triethylsilane (0.86 mL, 5.40 mmol) and methanol (0.43 mL, 10.6 mmol) at 0° C. was added trifluoroacetic acid (2.2 mL, 28.6 mmol), and the resulting solution was stirred at 25° C. for 14 h After dilution with ether (30 mL), saturated NaHCO3 was added until the aqueous phase was rendered basic. The aqueous layer was extracted with ether (10 mL), and the combined ether layers were washed with water (10 mL) and brine (10 mL), and dried (Na2SO4). Concentration gave the crude product which was purified by radial PLC (silica gel, 5% ethyl acetate/hexanes) to afford 2-chloro-4-iodo-6-methoxy-5-(methoxymethyl)pyridine as a white solid (1.05 g, 93%): mp 69°-72° C. Recrystallization from hexanes provided an analytical sample: mp 74°-75° C. 1H NMR (300 MHz, CDCl3) δ 7.40 (S, 1H), 4.53 (s, 2H), 3.96 (s, 3H), 3.42 (s, 3H); IR (nujol) 1550, 1300, 1115, 1090, 1020, 940, 905, 830, 720 cm-1.

Workup

  1. additionwas added until the aqueous phase
  2. extractionThe aqueous layer was extracted with ether (10 mL)
  3. washthe combined ether layers were washed with water (10 mL) and brine (10 mL)
  4. dry with materialdried (Na2SO4)
  5. concentrationConcentration
  6. customgave the crude product which
  7. customwas purified by radial PLC (silica gel, 5% ethyl acetate/hexanes)

Sources & evidence

ORD record
ord-7cd1ceb789a64509998b2fb82e19ba0c
Source dataset
uspto-grants-1992_11
Patent number
US05162532

Reaction notes

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