Remote Rotamer Control: The Effect of a 4-tert-Butyl Group on the Coordination Chemistry of TpR Ligands

✍ Scribed by Arnold L. Rheingold; Louise M. Liable-Sands; James A. Golan; Swiatoslaw Trofimenko

• Publisher: John Wiley and Sons
• Year: 2003
• Tongue: English
• Weight: 165 KB
• Volume: 2003
• Category: Article
• ISSN: 1434-1948
• DOI: 10.1002/ejic.200300005

✦ Synopsis

Abstract

Three novel homoscorpionate ligands containing a tert‐butyl group in the 4‐position have been synthesized: hydrotris(4‐tert‐butylpyrazol‐1‐yl)borate (Tp^4^^t^^Bu^), hydrotris(4‐tert‐butyl‐3‐p‐tolylpyrazol‐1‐yl)borate (Tp^Tol,4^^t^^Bu^), and hydrotris(4‐tert‐butyl‐3‐isopropylpyrazol‐1‐yl)borate (Tp^i^^Pr,4^^t^^Bu^). The 4‐tert‐butyl group does not alter the coordination chemistry of the first two ligands, relative to their 4‐H analogues, however, the coordination chemistry of the third ligand is dramatically changed, making it a “tetrahedral enforcer”. The complexes Co[Tp^4^^t^^Bu^][Tp^Np^] (1), Tl[Tp^Tol,4^^t^^Bu^] (2), RhTp^Tol,4^^t^^Bu^~2~ (3), Co[Tp^i^^Pr,4^^t^^Bu^]Cl (4), Co[Tp^i^^Pr,4^^t^^Bu^]N~3~ (5) and Co[Tp^i^^Pr,4^^t^^Bu^]NCS (6) have been structurally characterized. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)