Navigation

0 Hits

  • Previous / Next

You are using Science Of Synthesis as a Guest.
Please login or sign up for a free trial to access the full content.
31.25.1.1.2.2 Method 2: Condensation of Nitrosoarenes with Arylamines in the Presence of a Base

DOI: 10.1055/sos-SD-031-01625

Rück-Braun, K.; Dietrich, S.; Kempa, S.; Priewisch, B.Science of Synthesis, (2007311459.

The condensation of nitrosoarenes with pyridin-2-amine to yield the corresponding hetaryldiazenes fails in pure glacial acetic acid, probably due to protonation of the nitrogen atom in the aromatic ring.[‌225‌] On the other hand, condensation of aryl and hetaryl nitroso compounds with pyridinamines and a series of other hetarylamines in aqueous sodium hydroxide furnishes the corresponding nitrogen-containing hetaryldiazenes 117, often in good yields (Scheme 52).[‌225‌‌229‌] In the absence of an arylamine, nitrosoarenes form diaryldiazene oxides under oxygen-free conditions, or nitroarenes in the presence of oxygen in an alkaline medium.[‌230‌] Therefore, the reaction is often carried out by gradually adding the nitroso compound to a solution of the arylamine in 50% aqueous sodium hydroxide over a period of 1030 minutes at a temperature between 60°C and reflux. In contrast to the condensation reaction in acetic acid, in an alkaline medium the reaction rate is enhanced by electron-withdrawing groups in the arylamine, while electron-releasing groups decrease it. In the nitroso compound, this effect of substituents on the reaction rate is reversed.[‌231‌] A drawback of the method is that toxic benzene is used as a cosolvent in many cases.

Meeeee 88 Meeeeeeeeeee ee Meeeeeeeeeee Meeeeeeeee eeee Meeeeeeeeeeee ee ee Meeeeeee Meeeee[‌888‌‌888‌]

Meeeeeeeeee 88

Me8 Me8 Meeee (Me8MM/Me8MM8) Meeeeeeeee Meeee (%) Mee
Me 8-eeeeeee 8.88:8 88% ee MeMM/eeeeeee (88:8), eeee, 88eee 88 [‌888‌]
eeeeeee-8-ee 8:8 88% ee MeMM, eeeeee, 8e 88 [‌888‌]
8-eeeeeee 8:8 88% ee MeMM, eeeeee, 8e 88 [‌888‌]
8:8 88% ee MeMM, eeeeee, 8e 88 [‌888‌]
Me 8.88:8 88% ee MeMM/eeeeeee (88:8), 88°M, 88eee 88 [‌888‌]
Me 8.88:8 88% ee MeMM/eeeeeee (88:8), 88°M, 88eee 88 [‌888‌]
Me 8.88:8 88% ee MeMM/eeeeeee (88:8), 88°M, 88eee 88 [‌888‌]
Me 8.88:8 88% ee MeMM/eeeeeee (8.8:8), eeeeee, 88eee 88 [‌888‌]

Mee eeee-eeeeeeeee eeeeeeeeeeee eee eeee ee eeeeeee ee eee eeeeeeeee ee eee eeeeeeeeeeeeee 888. Mee eeeee eeeeeeeee, eeeeeeeee eeee-eeeeeeee ee e eeeeeee ee eeeeeeee eeeeeeeee eee eeee-eeeee eeeeeee ee e 8.88% eeeeeee eeeeeeee ee eeeeee eeeeeeeee ee 8888°M eee eeeeeeee (Meeeee 88).[‌888‌‌888‌] Mee eeeee eeeeeeeee ee e eeeeee eeeeeeeeeee ee ee e eeeeeee eeeeeeeeeeeee ee eeeeee eeeeeeeee.[‌888‌]

Meeeee 88 Meeeeeeeeeee ee Meeeeeeeee eeee Meeeeeeeeeeee eeeee Meeee Meeeeeeeee[‌888‌‌888‌]

Meeeeeeeeee 88

Me8 Me8 Meeee (Me8MM/Me8MM8) Meeeeeeeee Meeee (%) Mee
Me 8-MeM8M8 8:8 e-MeMM, MMMM/e-MeMM (8:8), 88°M, 88eee 88 [‌888‌]
Me 8-MeM8M8 8:8 e-MeMM, MMMM/e-MeMM (8:8), 88°M, 88eee 88 [‌888‌]
Me 8:8 e-MeMM, MMMM/e-MeMM (8:8), ee, 88eee 88 [‌888‌]
8-Mee 8-M8MMM8M8M8 8:8 8.8% ee MeMM, 88°M, 8e 88 [‌888‌]
8-Mee 8-M8MMM8M8M8 8:8 8% ee MeMM, 88°M, 8.8e 88 [‌888‌]
8-Mee 8-M8MMM8M8M8 8.8:8 8.8% ee MeMM, 88°M, 8e 88e [‌888‌]

e Meeeeeeee 8-eeeeeeeeeeeeee eee eeeeeeeee.

Meeeeeeeeeee Meeeeeeee:

8-Meeeee-8-eeeeee-8-(8-eeeeeeeeeeeeeee)-8M-eeeeeee-8-eeeee (888, Me8=8-Meeee-8-eeeeee-8-eeeeee-8M-eeeeeee-8-ee; Me8=8-Meeeeee); Meeeeee Meeeeeeee:[‌888‌]

Me e eeeeeee ee 8-eeeeee-8-eeeeeee-8-eeeeee-8M-eeeeeee-8-eeeee (8.88e, 8.88eee) eee eeeeeee-8-eeeee (8.88e, 8.88eee) eee eeeee 88% ee MeMM (88eM). Mee eeeeeee eee eeeeeeee eee 8e. Meeee eeeeeee ee ee, ee eee eeeeee eeee eeeeeee eee (88e) eeee eeeeeeee eeeeeeee. Mee eeeeeeeeeee eee eeeeeeeee ee eeeeeeeeee, eeeeee eeee M8M ee eeeeee eeeeee, eee eeeee. Meeeeeeeeeeeeeeee (MeMM/MMM 8:8) eeee ee eeeeee eeeeeeeeeee eeeee; eeeee: 8.88e (88%); ee 888°M.

References


Cookie-Einstellungen