Extremely Electron-Rich, Boron-Functionalized, Icosahedral Carborane-Based Phosphinoboranes
datasetposted on 2012-12-24, 00:00 authored by Alexander M. Spokoyny, Calvin D. Lewis, Georgiy Teverovskiy, Stephen L. Buchwald
We have prepared the first examples of B9-connected trivalent aryl and alkyl phosphinoborane species via Pd-catalyzed phosphination of 9-iodo-meta-carborane. Our studies highlight the unique electronic features of the B9-connected meta-carboranyl moiety as compared to its C1-based analogue. This work suggests that the B9-functionalized meta-carboranyl substituent in these ligands exhibits more electron-releasing character than any other known carbon-based substituent, ultimately laying the foundation for a new class of phosphine ligands with extremely electron-rich character.