Chloroform → methyl 11-methyl-6H-pyrido[4,3-b]carbazole-5-carboxylate

HRID 232180Notes

Reaction equation

HRID 232180 reaction equation
[Na].[Br-].[N+](C1C=CC(C[N+:11]2[CH:32]=[CH:31][C:14]3=[C:15]([C:27]([O:29][CH3:30])=[O:28])[C:16]4[NH:17][C:18]5[CH:19]=[CH:20][CH:21]=[CH:22][C:23]=5[C:24]=4[C:25]([CH3:26])=[C:13]3[CH:12]=2)=CC=1)([O-])=O.N(C1C=CC(N(C)C)=CC=1)=O.C(Cl)(Cl)Cl>CO>[C:27]([C:15]1[C:16]2[NH:17][C:18]3[CH:19]=[CH:20][CH:21]=[CH:22][C:23]=3[C:24]=2[C:25]([CH3:26])=[C:13]2[CH:12]=[N:11][CH:32]=[CH:31][C:14]=12)([O:29][CH3:30])=[O:28]

Participants

6

Reactant 4

HCID 6212ChloroformHCID 8749N,N-Dimethyl-4-nitrosoanilineHCID 5360545SodiumHCID 138089602-(p-Nitrobenzyl)-5-carbomethoxy-11-methyl-6H-pyrido [4,3-b] carbazolium Bromide

Product 1

HCID 13808962methyl 11-methyl-6H-pyrido[4,3-b]carbazole-5-carboxylate

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

To a solution of 200 mg (13 mmol) of metallic sodium in 600 mL of dry MeOH there were added 2.70 g (5.3 mmol) of the quaternary salt 22, 1.06 g (6.3 mmol) of p-nitrosodimethylaniline, and 300 mL of dry CHCl3. The suspension was stirred overnight at room temperature in a nitrogen atmosphere and then evaporated to dryness. The residue was suspended in a solution of 30 mL of CHCl3 and 5 mL of MeOH and flash chromatographed on a column of 40 g of silica gel with ether-triethylamine (20:1) as the eluant. The purest fraction was set aside and the less pure material was rechromatographed. The process was repeated, and the purest fractions which showed essentially only one spot on TLC were combined; wt 715 mg (47%). After crystallization from EtOAc-CH2Cl2 (5:1), the yellow needles melted at 203°-204° C. dec: NMR (Me2SO-d6) 11.56 (s, 1 H), 9.73 (s, 1 H), 8.87 (d, 1 H), 8.53 (d, 1 H), 8.38 (d, 1 H), 7.80 (d, 1 H), 7.60-7.52 (m, 1 H), 7.30-7.29 (m, 1 H), 4.10 (s, 3 H), 3.33 (s, 3 H); IR (KBr) 3300, 2950, 1675, 1600, 1465 cm-1.

Workup

  1. customevaporated to dryness
  2. customchromatographed on a column of 40 g of silica gel with ether-triethylamine (20:1) as the eluant
  3. customthe less pure material was rechromatographed
  4. customAfter crystallization from EtOAc-CH2Cl2 (5:1)

Sources & evidence

ORD record
ord-71b580decefb431da1e670d2bb082059
Source dataset
uspto-grants-1989_07
Patent number
US04851417

Reaction notes

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