The infrared and Raman spectra of carbonyl diisocyanate

Photolysis of Carbonyl Diisocyanate: Generation of Isocyanatocarbonyl Nitrene and Diazomethanone

“…[5] In addition to the bands forC O, OCNC(O)N, and OCNNCO, av ery weak band was observed at 1839.6 cm À1 (not labeled; Figure 4) in the IR spectrum of the ArF-laser photolysis products of OC(NCO) 2 .T he position of this band was very close to the known IR frequency of NOCN (1836.9 cm À1 )f or the NO stretching vibration. [24] To confirmt he assignment of this weak band,a ni ndependent Ar matrix that contained a 15 N-enriched OCNNCO sample, which was prepared by the photolysis of 15 N-enriched OC(N 3 ) 2 in aC O-doped matrix, was irradiated with a1 93 nm ArF laser.T he decomposition of OCNNCO ( Figure 6, bandsc)i nto NOCN ( Figure 6, bands d; 15 Ni sotope shift of 32.4 cm À1 )w as evident, as showni nt he IR differences pectrum ( Figure 6). In addition, 15 Ni sotope shifts of 6.3 and 5.2 cm À1 for the strongestI Rb and (n 9 ;2 201.4 cm À1 )o fO CNNCO ware obtained for the first time.…”

“…[24] To confirmt he assignment of this weak band,a ni ndependent Ar matrix that contained a 15 N-enriched OCNNCO sample, which was prepared by the photolysis of 15 N-enriched OC(N 3 ) 2 in aC O-doped matrix, was irradiated with a1 93 nm ArF laser.T he decomposition of OCNNCO ( Figure 6, bandsc)i nto NOCN ( Figure 6, bands d; 15 Ni sotope shift of 32.4 cm À1 )w as evident, as showni nt he IR differences pectrum ( Figure 6). In addition, 15 Ni sotope shifts of 6.3 and 5.2 cm À1 for the strongestI Rb and (n 9 ;2 201.4 cm À1 )o fO CNNCO ware obtained for the first time.…”

“…Carbonyl diisocyanate (OC(NCO) 2 ), [15] carbonyl diazide (OC(N 3 ) 2 ), [5] azidoisocyanate (NNNNCO), [6] and diazirinone (cyclo-N 2 CO) [8b] were prepared according to literature procedures. 15 N-labeled OC(N 3 ) 2 was synthesized by using 1- 15 Nsodium azide (98 atom % 15 N; EURISO-TOP GmbH). The quality of these samples was checked by using gas-phase IR spectroscopy.…”

“…In contrast to OC(N 3 ) 2 and N 3 C(O)NCO, carbonyl diisocyanate, OC(NCO) 2 , is fairly stable and can be distilled . At room temperature, it trimerizes into a white solid from which the monomer can be recovered by heating without noticeable decomposition.…”

“…In contrast to OC(N 3 ) 2 and N 3 C(O)NCO, carbonyl diisocyanate, OC(NCO) 2 ,i sf airly stable and can be distilled. [15] At room temperature, it trimerizes into aw hite solidf rom which the monomer can be recovered by heating withoutn oticeable decomposition. According to gas electron diffraction (GED) and vibrational spectroscopy studies, [16] OC(NCO) 2 has two conformers, syn-syn and syn-anti,i nb oth the liquid and gas phases;h owever,n oi nformation regarding conformationali nterconversion was reported.…”