Nitric Acid → 6-Nitrobenzo[d]thiazole-2-carbonitrile

HRID 2044138Notes

Reaction equation

HRID 2044138 reaction equation
[C:1]([C:3]1[S:4][C:5]2[CH:11]=[CH:10][CH:9]=[CH:8][C:6]=2[N:7]=1)#[N:2].[N+:12]([O-])([OH:14])=[O:13]>OS(O)(=O)=O>[C:1]([C:3]1[S:4][C:5]2[CH:11]=[C:10]([N+:12]([O-:14])=[O:13])[CH:9]=[CH:8][C:6]=2[N:7]=1)#[N:2]

Participants

4

Reactant 2

HCID 944Nitric AcidHCID 6385601,3-benzothiazole-2-carbonitrile

Product 1

HCID 106320416-Nitrobenzo[d]thiazole-2-carbonitrile

Reagents, catalysts & solvents 1

HCID 1118Sulfuric AcidSolvent

Procedure

In particular 2-cyano-benzothiazole 10 (0.84 mmol, 0.134 g) was suspended in 0.563 ml conc. H2SO4 at 0° C. 1.3 equivalents of concentrated HNO3 (1.1 mmol, 0.069 g) was added portionwise over 10 min to the stirring solution; not to exceed 0° C. over a total of ˜45 min. The reaction proceeded further for 2 h and at 5 h the product was evident. The reaction was then poured over ice/water, extracted into EtOAc, and concentrated in vacuo to yield a crude yellow residue 11. For analytical characterization, a small portion was purified by semi-preparative HPLC at 10 mL/min on a Waters preparative machine (Waters Symmetry prep C18, 7 μm, 19×300 mm column, photodiode array detection) with a linear gradient from 90% H2O (0.1% TFA) to 50% MeCN (0.1% TFA) for 30 min yielding a large product peak at ˜27 minutes. The fractions were collected and lyophilized using Kinetics Flexi-Dry freeze-dryer.

Workup

  1. customto exceed 0° C. over a total of ˜45 min
  2. extractionextracted into EtOAc
  3. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-f87fa53686c64085b836c1577553e94b
Source dataset
uspto-grants-2013_11
Patent number
US08586759B2

Reaction notes

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