BORYLS BOUND TO IRON CARBONYL - STRUCTURE OF A RARE BIS(BORYL) COMPLEX, SYNTHESIS OF THE FIRST ANIONIC BORYL, AND REACTION CHEMISTRY THAT INCLUDES THE SYNTHETIC EQUIVALENT OF BORYL ANION TRANSFER

The synthesis, structure, and reaction chemistry of iron carbonyl bory l complexes are described. Bis(boryl) complexes were prepared by react ion of Na-2[Fe(CO)(4)] with chlorocatecholborane and substituted chlor ocatecholboranes. An X-ray diffraction study of [Fe(CO)4-(BCat)(2)] ( BCat = -BO2C6H3-4-t-Bu) was performed and showed significant distorti ons from octahedral geometry. These bis(boryl) complexes underwent exc hange reactions with alcohols, amines, and silylamides. They were conv erted to anionic compounds by reaction with LiN(SiMe(3))(2), and these anionic boryls are the first such examples. The anionic character all owed for nucleophilic substitutions. These complexes reacted with ClSn Me(3) to yield a mixed boryl-stannyl compound in high yield. In contra st, reaction with methyl iodide or methyl triflate did not lead to an isolable alkylboryl complex. Instead, rapid formation of MeBCat occurr ed, a rare transformation that substitutes a boryl group for halide.