Patent ID: 6410764
Filing Date: 2002-06-25
Classification: C07F

Abstract:
A process for the preparation of a boratabenzene complex having the formula: whereM is a metal selected from Groups 4 to 10 of the Periodic Table; n is such that the complex (I) is neutral; each X individually is a halogen, a C1-8 alkyl group, a C6-10 aryl group, a C7-15 aralkyl group, a C1-10 alkoxy group, or a C1-10 dialkylamino group, each of these groups optionally substituted with one or more halogens, cyano groups, C1-4 alkoxy groups, or C1-4 alkyl groups; L1 is a hydrogenated boranaphthalene ligand with the structure: â€ƒwhere R1 is hydrogen, a C1-8 alkyl group, a C6-10 aryl group, a C7-15 aralkyl group, a C1-10 alkoxy group, a C6-14 aryloxy group, a C1-8 dialkylamino group, or a C6-15 diarylamino group; each R2 individually is a C1-8 alkyl group or a C6-10 aryl group; m is 0 to 4; and L2 is a second hydrogenated boranaphthalene ligand, a boratabenzene ligand, or an optionally substituted cyclopentadienyl ring; said process comprising hydrogenating a boranaphthalene compound with hydrogen in the presence of a hydrogenation catalyst to form said hydrogenated boranaphthalene ligand(s), said process comprising at least one of the alternatives a) through c):a) selecting as said boranaphthalene compound a compound having the structure: â€ƒwhere M is a metal selected from Groups 4 to 10 of the Periodic Table; n is such that the complex (IV) is neutral; each X independently is a halogen, a C1-8 alkyl group, a C6-10 aryl group, a C7-15 aralkyl group, a C1-10 alkoxy group, or a C1-10 dialkylamino group, each of these groups optionally substituted with one or more halogens, cyano groups, C1-4 alkoxy groups, or C1-4 alkyl groups, â€ƒwhere L3 is a boranaphthalene ligand having the structure: â€ƒwherein L4 is L3 or is a boratabenzene ligand, or an optionally substituted cyclopentadienyl ring, and hydrogenating said compound (IV) to form said boratabenzene complex (I); b) selecting as said boranaphthalene compound a compound having the formula: and hydrogenating said boranaphthalene compound (V) to form a boratabenzene complex having the formula: and reacting said boratabenzene complex VI with a compound of the formula:L4&ominus;AâŠ•â€ƒâ€ƒ(VII) wherein AâŠ• is the cation of a strong base, and L4&ominus; is a boranaphthalene anion, a hydrogenated boranaphthalene anion, a boratabenzene anion, or a cyclopentadienyl anion, all of said anions optionally substituted, to form said boratabenzene complex of the formula (I);c) selecting a boranaphthalene compound having the formula: hydrogenating said boranaphthalene compound (IIIâ€²) to form a hydrogenated boranaphthalene compound having the formula: reacting said hydrogenated boranaphthalene compound (IIâ€²) with a metal complex having the formula: to form a boratabenzene complex of the formula (I).