2-phenyldiazenylaniline

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of the aminoazobenzene (1 eq) and DIPEA (2 eq) in 1:1 MeCN:DMF at 0° C. was added 2-triethylammonium acetic acid chloride chloride8 (1.5 eq) in 1:1 MeCN:DMF and stirred for 15 min, then warmed to ambient temperature and stirred for 1-12 h at which time the solvent was removed in vacuo for purification by reverse phase silica gel chromatography (0.1% formic acid in H2O, gradient up to 50% MeCN: 0.1% formic acid in H2O). was removed in vacuo for purification by reverse phase silica gel chromatography (0.1% formic acid in H2O, gradient up to 50% MeCN: 0.1% formic acid in H2O)

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: In the examples which follow, the yield of benzenediazonium salt was determined by reacting the benzenediazonium solution with aniline and then rearranging the intermediate triazene to give aminoazobenzene. Thus, the solution containing the diazonium salt was charged into a mixture containing aniline, in large excess (5 to 7 times the theoretical amount), aniline hydrochloride, in half the stoichiometric amount relative to the aniline, and water. The mixture was maintained at 50° C. and aminoazobenzene (ortho and para isomers) was obtained very rapidly in quantitative yield. The excess aniline hydrochloride was then neutralized, the aniline and the aminoazobenzene were extracted with ethyl acetate, and the ethyl acetate and the aniline were distilled. This yields crude aminoazobenzene (ortho+para), the composition of which was determined by vapor phase chromatography.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: In a method for preparing the compound: ##STR3## wherein aniline is diazotized in aqueous hydrochloric acid employing sodium nitrite as the diazotizing agent to form benzenediazonium chloride, the benzenediazonium chloride is coupled into aniline to form aminoazobenzene, and the aminoazobenzene is diazotized and coupled into phenol; the improvement comprising: diazotizing the aniline employing an excess of sodium nitrite of up to about 10% of the amount stoichiometrically required to diazotize one-half of the aniline on a molar basis; coupling the resultant benzenediazonium chloride with the remaining aniline to form a mixture of aminoazobenzene and excess benzenediazonium chloride in aqueous hydrochloric acid; heating said mixture to about 40° C. and allowing said excess benzenediazonium chloride to decompose and, subsequently, without isolation, diazotizing said aminoazobenzene and coupling it into phenol.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of the aminoazobenzene (1 eq) and DIPEA (2 eq) in 1:1 MeCN:DMF at 0° C. was added 2-triethylammonium acetic acid chloride chloride8 (1.5 eq) in 1:1 MeCN:DMF and stirred for 15 min, then warmed to ambient temperature and stirred for 1-12 h at which time the solvent was removed in vacuo for purification by reverse phase silica gel chromatography (0.1% formic acid in H2O, gradient up to 50% MeCN: 0.1% formic acid in H2O). was removed in vacuo for purification by reverse phase silica gel chromatography (0.1% formic acid in H2O, gradient up to 50% MeCN: 0.1% formic acid in H2O)