Ligand-Induced and Reductively Induced Alkyne-Isocyanide Coupling Reactions of [Mo(CNBut)3(PhCCPh)(g src="ht
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- 作者：Christopher J. Adams ; Kirsty M. Anderson ; Ian M. Bartlett ; Neil G. Connelly ; A. Guy Orpen ; and Timothy J. Paget
- 刊名：Organometallics
- 出版年：2002
- 出版时间：August 5, 2002
- 年：2002
- 卷：21
- 期：16
- 页码：3454 - 3463
- 全文大小：143K
- 年卷期：v.21,no.16(August 5, 2002)
- ISSN：1520-6041
文摘
The complex [Mo(CO)(PhCG SRC="/images/entities/tbd1.gif">CPh)2(
ges/gifchars/eta.gif" BORDER=0 >5-C5Me5)][BF4] reacts with 3 equiv of CNBut to yieldthe mixed alkyne-isocyanide complex [Mo(CNBut)3(PhCges/entities/tbd1.gif">CPh)(ges/gifchars/eta.gif" BORDER=0 >5-C5Me5)][BF4], 1. Reactionof 1 with a fourth equivalent of CNBut generates [Mo{=C(NHBut)C(Ph)=C(Ph)CN}(CNBut)2(ges/gifchars/eta.gif" BORDER=0 >5-C5Me5)][BF4], 2, containing an ges/gifchars/eta.gif" BORDER=0 >3-vinylcarbene ligand formed from the coupling of two ofthe coordinated isocyanide ligands with the diphenylacetylene, with concomitant protonationof one of these isocyanide fragments and dealkylation of the other. Complex 2 may bedeprotonated to give [Mo{C(=NBut)C(Ph)=C(Ph)CN}(CNBut)2(ges/gifchars/eta.gif" BORDER=0 >5-C5Me5)], 3. Protonation of1 with HBF4·Et2O generates [Mo{=C(Ph)C(Ph)C=NHBut}(CNBut)2(ges/gifchars/eta.gif" BORDER=0 >5-C5Me5)][BF4]2, 4, byinducing the coupling of a protonated isocyanide ligand with diphenylacetylene, and 4 reactswith CNBut to give 2. A similar reaction of 4 with P(OMe)3 generates [Mo{=C(NHBut)C(Ph)=C(Ph)CN}(CNBut){P(OMe)3}(ges/gifchars/eta.gif" BORDER=0 >5-C5Me5)][BF4], 5, involving the same coupling andelimination pattern. The diphenylacetylene and CNBut ligands of 1 may also be reductivelycoupled. Thus, treatment of 1 with sodium-mercury amalgam and subsequent protonationwith HBF4·Et2O gives the metallacyclopentatriene-like [Mo{=C(NHBut)C(Ph)=C(Ph)C(NHBut)}(CNBut)(ges/gifchars/eta.gif" BORDER=0 >5-C5Me5)][BF4], 6, or [Mo{=C(NHBut)C(Ph)C(Ph)CH-NHBut}(CNBut)(ges/gifchars/eta.gif" BORDER=0 >5-C5Me5)][BF4], 7, depending upon the solvent. Complex 7 contains an N-protonated ges/gifchars/eta.gif" BORDER=0 >4-monoazadiene ligand with a pendant carbene functionality that is also coordinated to themetal. The crystal structures of 1, 2, 3, 6, and 7 have been determined.