Open AccessExpanding the Scope of Palladium-Catalyzed B–N Cross-Coupling Chemistry in Carboranes
Author(s) -
Xin Mu,
Morgan Hopp,
Rafal M. Dziedzic,
Mary A. Waddington,
Arnold L. Rheingold,
Ellen M. Sletten,
Jonathan C. Axtell,
Alexander M. Spokoyny
Publication year - 2020
Publication title -
organometallics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.231
H-Index - 172
eISSN - 1520-6041
pISSN - 0276-7333
DOI - 10.1021/acs.organomet.0c00576
Subject(s) - chemistry , carborane , nucleophile , substituent , steric effects , palladium , reactivity (psychology) , sulfonamide , combinatorial chemistry , cluster (spacecraft) , stereochemistry , catalysis , medicinal chemistry , organic chemistry , computer science , programming language , medicine , alternative medicine , pathology
Over the past several years, a number of strategies for the functionalization of dicarba- closo -dodecaboranes (carboranes) have emerged. Despite these developments, B - N bond formation on the carborane scaffold remains a challenge due to the propensity of strong nucleophiles to partially deboronate the parent closo -carborane cluster into the corresponding nido form. Here we show that azide, sulfonamide, cyanate, and phosphoramidate nucleophiles can be straightforwardly cross-coupled onto the B(9) vertices of the o - and m -carborane core from readily accessible precursors without significant deboronation by-products, laying the groundwork for further study into the utility and properties of these new B-aminated carborane species. We further showcase select reactivity of the installed functional groups highlighting some unique features stemming from the combination of the electron-donating B(9) position and the large steric profile of the B-connected carborane substituent.