Diamidophosphites with isomeric carborane fragments: a comparison of catalytic activity in asymmetric Pd-catalyzed allylic substitution reactions
2010; Elsevier BV; Volume: 51; Issue: 13 Linguagem: Inglês
10.1016/j.tetlet.2010.01.084
ISSN1873-3581
AutoresS. E. Lyubimov, В. А. Даванков, Konstantin N. Gavrilov, Tatiana B. Grishina, E. A. Rastorguev, Andrey A. Tyutyunov, T. A. Verbitskaya, V. N. Kalinin, Evamarie Hey‐Hawkins,
Tópico(s)Chemical Synthesis and Analysis
ResumoNew chiral diamidophosphite ligands containing electron-donating 9-meta-carborane and electron-withdrawing 1-meta-carborane substituents have been synthesized. The ligand 3a with an electron-donating group demonstrated high enantioselectivity in Pd-catalyzed allylic substitution reactions with C-, S- and N-nucleophiles (up to 98% ee). The isomeric diamidophosphite 3b bearing an electron-withdrawing substituent showed in all cases, moderate-to-poor conversion and lower enantioselectivity.
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