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Vol. 66358 mp, whereas a t the 3-position it shifts the 355 mp max. to 278 mp. The band at 3.55 mp varies little with substitution, and the band a t 240 mp varies from 235-252 with substitution. Electron donating groups on the aryl groups in the pyrazoline ring shift the 240 mp maximum to longer wave lengths.Introduction of another double bond in the 1,3,5triphenyl-2-pyrazoline nucleus leads t o a pyrazole which does not absorb a t 350-360 mp but has only one strong band a t 250 mp (emax 30,800). It is significant to note here that the ultraviolet h,,, of 240 mp is present in unsubstituted 2-pyra~oline.'~ The infrared spectra of the 2-pyrazolines were examined in the 2-15 p region and the results are shown in Table V. The single strong band at 6.25 to 6.27 p probably is due to both the C=N and aromatic C=C stretching vibration, as also has been noted in an earlier report.* I n general, the fingerprint regions of the 2-pyrazolines are very similar. (12) K. V. Auwers and H. Hollmann, Ber., 69B, 601 (1926).Active nitrogen has been found to destroy ammonia a t -196" to produce hydrazine which in turn is destroyed. Possible reaction sequences are proposed to account for the results.

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