کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5416258 1506883 2010 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Why Lewis acids accelerate the thermal Curtius rearrangement of benzoyl azide into phenyl isocyanate
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی تئوریک و عملی
پیش نمایش صفحه اول مقاله
Why Lewis acids accelerate the thermal Curtius rearrangement of benzoyl azide into phenyl isocyanate
چکیده انگلیسی
The thermal Curtius rearrangement of benzoyl azide in the presence of Lewis acids has been studied by DFT (PBE/TZ2P) method. The complexation of Lewis acids (BF3, AlCl3, SbCl5) with benzoyl azide leads to the formation of 1:1 and 1:2 stable complexes with interaction of catalysts with O and N atoms of carbonyl azide group. The potential energy surfaces of the catalytic rearrangement have been calculated for each complex and the relation between the complexes and the transition states on potential energy surface have been established by IRC calculation. The energy barriers for catalytic reactions are significantly lower in the most cases in comparison with an uncatalyzed reaction. The activation energy is decreasing in the range of Lewis acids AlCl3 > SbCl5 > BF3 and it correlates with the decreasing of Lewis acids strength. The Mulliken bond population analysis has been done for three compounds RCON3 (R = H, Me, Ph) and for their complexes, and for all corresponding transition states using the B3LYP/6-311G∗ approximation. The interaction of Lewis acids with carbonyl azide group causes the decreasing of N1N2 bond strength and it helps the thermal Curtius rearrangement to proceed.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Molecular Structure: THEOCHEM - Volume 962, Issues 1–3, 30 December 2010, Pages 15-22
نویسندگان
, ,