Nitrilimine, 1,3-diphenyl-, cycloaddition

The reactivity and regioselectivity of the cycloaddition of l-(A-phenacylidene)amino-1,2,3-triazoles with diphenyl nitrilimine (see Section 4.01.7.4) are examined on the basis of CNDO/2 calculations. The cycloaddition regioselectivity is HOMOjdipoie) controlled. The predominant orbital interaction shown in Figure 1 rationalizes the regioselective formation of 277-1,2,3-triazoles... 

Dipolar cycloadditions to azepines are confined to diazomethane and diphenyl-nitrilimine. The former reagent, depending on the nature of the substituents on the H-azepine, either adds at the 4,5-bond to yield pyrazolines (160) or traps the benzeneimine tautomer of the azepine as the bis-pyrazoline (Section 5.16.2.4) (76CB3505). A pyrazoline is also the product from the addition of diphenylnitrilimine to 5//-dibenz[i,/]azepine (B-67MI51600). 

Photolysis of oxadiazolinone (lOf) yields a nitrilimine (Ilf) which, in the presence of alkenes, undergoes cycloaddition to give pyrazoles (68TL325). Azobenzene is produced on irradiation of 3,4-diphenyl-l,3,4-oxadiazolidine-2,5-dione. 

Die dipolare Cycloaddition von Diphenyl-nitrilimin mit einigen Alkinen, wie Phenyl-ethin oder Phenyl-ethinylmagnesiumbromid zu 1,3,5-Triphenyl-1 H-pyrazol, Ethinyl-magnesiumbromid zu 1,3-Diphenyl-1 H-pyrazol und Propinsaure-methylester zu 1,3-Diphenyl-5-methoxycarbony 1-1H-pyrazol, wird im Bd.X/2, S. 510-514 (1967) u. XIII/2a, S.469 (1973) behandelt. 

The novel tricyclic system (55) was prepared by the 1,3-dipolar cycloaddition of 1,3-diphenyl-nitrilimine to the G=N double bond of (34a) <83UC(B)627>. 

Table 11.1 AljOj/KF-eatalysed 1, 3-dipolar cycloaddition of diphenyl nitrilimine (DPNl)...

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