Table 1: Physical data for the N-(2,3-dimethylphenyl)-N’-(aryl-diazenyl)-piperazines (3).
No |
X |
Crude |
Mp (℃) |
Recryst. |
Crystal |
IR (cm-1) |
yield |
|
Solv. |
Appearance |
|
|
(%) |
|
|
|
|
3a |
p-CN |
87.3% |
147-148 |
Ethanol |
Red-brown |
2220(CN) |
|
|
|
|
|
Needles |
848(para) |
|
|
|
|
|
|
785&724 |
|
|
|
|
|
|
(1,2,3-trisub) |
3b |
p-CO2CH3 |
63.7% |
155-157 |
Ethanol |
Small orange |
1714(C=O) |
|
|
|
|
|
Plates |
1275(C-O) |
|
|
|
|
|
|
856(para) |
|
|
|
|
|
|
780&724 |
|
|
|
|
|
|
(tri-sub) |
3c |
p-Br |
100.0% |
103-103.5 |
Ethanol |
Fibrous |
833(para) |
|
|
|
|
|
Off-white |
782&719 |
|
|
|
|
|
Plates |
(tri-sub) |
3d |
p-CH3 |
81.8% |
132-132.5 |
Ethanol |
Needles |
828(para) |
|
|
|
|
|
|
788&723 |
|
|
|
|
|
|
(tri-sub) |
3e |
p-NO2 |
100.0% |
152-155 |
Ethanol |
Red-brown |
1507 & |
|
|
|
|
|
Needles |
1341(NO2) |
|
|
|
|
|
|
851(para) |
|
|
|
|
|
|
787&721 |
|
|
|
|
|
|
(tri-sub) |
3f |
H |
57.7% |
102-102.5 |
Ethanol |
Lustrous |
697 & 763 |
|
|
|
|
|
Gold plates |
(mono-sub) |
|
|
|
|
|
|
788&724 |