Academic Journal
NMR and DFT Studies with a Doubly Labelled 15 N/ 6 Li S‐Trifluoromethyl Sulfoximine Reveal Why a Directedortho‐Lithiation Requires an Excess ofn‐BuLi
| العنوان: | NMR and DFT Studies with a Doubly Labelled 15 N/ 6 Li S‐Trifluoromethyl Sulfoximine Reveal Why a Directedortho‐Lithiation Requires an Excess ofn‐BuLi |
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| المؤلفون: | Hédouin, Matthieu, Barthelemy, Anne‐Laure, Vanthuyne, Nicolas, Besrour, Hend, Maddaluno, Jacques, Magnier, Emmanuel, Oulyadi, Hassan |
| المصدر: | Angewandte Chemie ; volume 135, issue 5 ; ISSN 0044-8249 1521-3757 |
| بيانات النشر: | Wiley |
| سنة النشر: | 2022 |
| المجموعة: | Wiley Online Library (Open Access Articles via Crossref) |
| الوصف: | This work shows why it is imperious to use an excess of butyllithium for a directed ortho ‐lithiation of a trifluoromethyl sulfoximine. The analysis of mixtures of n‐ BuLi and sulfoximine 1 in THF‐ d 8 using { 1 H, 6 Li, 13 C, 15 N, 19 F} NMR experiments at low temperatures reveal that a first deprotonation occurs that leads to dimeric and tetrameric N‐lithiated sulfoximine (93 : 7). Using an excess n ‐BuLi (5 equivalents), the second deprotonation on the ortho ‐position of the aromatic occurs. Six species were observed and characterized on the way. It includes three aggregates involving a sulfoximine: i) a [dilithiated sulfoximine/( n ‐BuLi)] dimer solvated by four molecules of THF ( Agg2 , 39 %); ii) a [dilithiated sulfoximine/( n ‐BuLi) 3 ] tetramer solvated by six molecules of THF ( Agg3 , 39 %); iii) a [dilithiated sulfoximine/( n ‐BuOLi) 3 ] tetramer solvated by four molecules of THF ( Agg1 , 22 %). A DFT study afforded optimized solvated structures for all these aggregates, fully consistent with the NMR data. |
| نوع الوثيقة: | article in journal/newspaper |
| اللغة: | English |
| DOI: | 10.1002/ange.202214106 |
| الاتاحة: | http://dx.doi.org/10.1002/ange.202214106 https://onlinelibrary.wiley.com/doi/pdf/10.1002/ange.202214106 https://onlinelibrary.wiley.com/doi/full-xml/10.1002/ange.202214106 |
| Rights: | http://creativecommons.org/licenses/by-nc-nd/4.0/ |
| رقم الانضمام: | edsbas.D723E5D0 |
| قاعدة البيانات: | BASE |
| DOI: | 10.1002/ange.202214106 |
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