TY - JOUR
T1 - Organotransition-metal Metallacarboranes. 11.1 chromium Tricarbonyl η6-complexes of Nido-2,3-(phch2)2c2b4h6
T2 - Metal Complexation And Oxidative Fusion
AU - Whelan, Thomas
AU - Spencer, James T.
AU - Pourian, Mohammad R.
AU - Grimes, Russell N.
PY - 1987/9/1
Y1 - 1987/9/1
N2 - The consequences of η6-phenyl coordination of Cr(CO)3groups on the chemistry of the C,C-dibenzylcarborane nido-2,3-(PhCH2)2C2B4H6(1) were investigated. The monochromium species [(CO)3Cr](PhCH2)2C2B4H6(2) underwent bridge (B-H-B) deprotonation by NaH in THF, and the resulting anion, on treatment with FeCl2, formed [[(CO)3Cr](PhCH2)2C2B4FI4]2FeH2(not isolated); subsequent oxidation with 02gave two isomers of [(CO)3Cr]2(PhCH2)4C4B8H8(7A,B), which were characterized spectroscopically. Reaction of the tetracarbon carborane (PhCH2)4C4BgH8(5) with Cr(CO)6gave dichromium products identical with 7A,B but no other isomers. An attempted analogous sequence with [(CO)3Cr]2(PhCH2)2C2B4H6(3) proceeded only as far as bridge deprotonation with KH; the resulting anion on treatment with FeCl2/O2did not undergo fusion, nor was fusion observed with other transition metals. An attempted mixed-ligand fusion of the anions of 1 and 3 gave only 5 and the original substrate 3. Deprotonation of 3 was shown to proceed cleanly, via deuteriation of the anion to produce monodeuteriated 3. The resistance of 3 to oxidative fusion is discussed in terms of steric and electronic effects.
AB - The consequences of η6-phenyl coordination of Cr(CO)3groups on the chemistry of the C,C-dibenzylcarborane nido-2,3-(PhCH2)2C2B4H6(1) were investigated. The monochromium species [(CO)3Cr](PhCH2)2C2B4H6(2) underwent bridge (B-H-B) deprotonation by NaH in THF, and the resulting anion, on treatment with FeCl2, formed [[(CO)3Cr](PhCH2)2C2B4FI4]2FeH2(not isolated); subsequent oxidation with 02gave two isomers of [(CO)3Cr]2(PhCH2)4C4B8H8(7A,B), which were characterized spectroscopically. Reaction of the tetracarbon carborane (PhCH2)4C4BgH8(5) with Cr(CO)6gave dichromium products identical with 7A,B but no other isomers. An attempted analogous sequence with [(CO)3Cr]2(PhCH2)2C2B4H6(3) proceeded only as far as bridge deprotonation with KH; the resulting anion on treatment with FeCl2/O2did not undergo fusion, nor was fusion observed with other transition metals. An attempted mixed-ligand fusion of the anions of 1 and 3 gave only 5 and the original substrate 3. Deprotonation of 3 was shown to proceed cleanly, via deuteriation of the anion to produce monodeuteriated 3. The resistance of 3 to oxidative fusion is discussed in terms of steric and electronic effects.
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U2 - 10.1021/ic00266a012
DO - 10.1021/ic00266a012
M3 - Article
AN - SCOPUS:33845282836
SN - 0020-1669
VL - 26
SP - 3116
EP - 3119
JO - Inorganic Chemistry
JF - Inorganic Chemistry
IS - 19
ER -