Preparation method of 2,4,6-tri-tert-butyronitrosobenzene_Kain Industrial Additive

Background and overview^[1]

2,4,6-Tri-tert-butylnitrosobenzene can be used as a pharmaceutical synthesis intermediate. If 2,4,6-tri-tert-butyl-nitrosobenzene is inhaled, please move the patient to fresh air; if the skin comes into contact, take off contaminated clothing and wash the skin thoroughly with soap and water. If you feel discomfort , seek medical attention; if eye contact occurs, separate eyelids, rinse with running water or saline, and seek medical attention immediately; if ingested, rinse mouth immediately, do not induce vomiting, and seek medical attention immediately.

Preparation^[1]

The preparation of 2,4,6-tri-tert-butyronitrosobenzene is as follows:

Dissolve TTBA (2,4,6-tri-tert-butylaniline, 127mM) in 3 ml MeOH, add [Mn (L) Cl2] complex (12.7mM) to the suspension in MeOH, and then Add H2O2 (127mM of 2,4,6-tri-tert-butylaniline). The above reaction was repeated using TBHP instead of H2O2 as the oxidant (2,4,6-tri-tert-butylaniline was 127mM). The reaction mixture was stirred in a water bath at a temperature of 45°C for 48 hours and monitored continuously using TLC. 2 spots were observed at different Rf values ​​and the reaction mixture was run on a short column after 48 hours and eluted with 20% ethyl acetate/hexane. Evaporation of the eluate to a small volume and holding overnight gave the desired product 2,4,6-tri-tert-butyronitrosobenzene. The above oxidation reaction can also use [Mn(L)(CH3COO)2] as a catalyst instead of [Mn(L)Cl2], but the product distribution obtained by using the [Mn(L)(CH3COO)2] complex as a catalyst is very complex, and the column Chromatography produced no separation of a single product. This may also explain why there are many products using [Mn(L)(CH3COO)2] as the oxidation catalyst to obtain hindered phenols and anilines.

1HNMR(d6-DMSO)(ppm):1.22(s,9H),1.38(s,18H),7.06(s,2H).13CNMR(d6-DMSO):168.0(C-1),142.1( C-4), 133.0 (C-2, C-6), 121.3 (C-3, C-5), 34.8 (C-7), 30.5 (C-8), 34.3 (C9), 32.0 (C- 10).ESIMS+(m/e):274,261,246,230.IR(cm1):1620,1363,%yield:75(Yieldsrefertoisolatedyield).

Main reference materials

[1] Organo-peroxyl compounds via catalytic oxidation of a hindered phenol and

aniline utilizing new manganese(II) bis benzimidazole diamide based complexes