کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1312767 975497 2007 5 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Experimental and calculated circular dichroism spectra of monoaza[5]helicenes
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی معدنی
پیش نمایش صفحه اول مقاله
Experimental and calculated circular dichroism spectra of monoaza[5]helicenes
چکیده انگلیسی

Circular dichroism (CD) spectra have been measured in the range of 400–200 nm on CH3OH solutions of both enantiomers for the almost complete series of monoaza[5]helicenes, namely the molecules where the hetero N atom occupies positions 1, 3, 4, 5, 6, and 7, respectively (the 2 isomer is missing due to difficulties in the synthesis). CD spectra recorded at controlled room temperature allow one to define precise racemization rates, that are nicely interpreted on the basis of DFT molecular orbital calculations. Time-dependent DFT methods provide us with calculated CD and UV spectra, that are compared with the corresponding experimental data. We discuss the role of the N atom in determining the height of the racemization barrier and in shaping the appearance of the CD spectra.

The rates of racemization the mono aza[5]helicenes were measured with the use of circular dichroism spectra, and the data interpreted on the basis of DFT molecular orbital calculations.Figure optionsDownload as PowerPoint slide

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Inorganica Chimica Acta - Volume 360, Issue 3, 15 February 2007, Pages 908–912
نویسندگان
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