During this research, the synthesis and use of 4-amino- and 4-hydroxy-1-allenylmetals have been studied.Two stereoselective and stereospecific syntheses of 4-sulfinamido- and 4-acetamido-1-allenylsilanes have been developed. These two synthetic routes rely on the reaction of lithium tris(dimethylphenylsilyl)zincate with acetylenic N-tert-butanesulfinylaziridines on one hand, and propargylic -acetamidoalkyl acetates on the other hand. The scope and limitations of these two complementary methods have been explored. The electrophilic fluorodesilylation reaction of 4-sulfinamido- and 4-acétamido-1-allenylsilanes with Selecfluor® gave access to propargylic -fluoroacetates in a stereoselective manner. A transition state model has also been postulated to explain the level of the chirality transfer observed. Finally, different synthetic routes towards 4-sulfinamido- and 4-sulfonylamido-1-allenylzincs through the 1,2-metalate rearrangement of acetylenic lithium tris(dimethylphenylsilyl)zincates, obtained from N-tert-butanesulfinyl- and N-tert-butanesulfonylaziridines, were proven to be unsuccessful. However, in the context of a French-Belgian collaboration, the study of the copper-catalyzed borylation of acetylenic epoxides led to promising results and paved the way for a new stereoselective synthesis of 4-hydroxy-1-allenylboranes.
|Translated title of the contribution||Allenylsilanes, allenylzincs and allenylboranes: stereoselective synthesis from propargylic electrophiles and study of their reactivity|
|Publication status||Unpublished - 17 Oct 2016|