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Room temperature ring-opening metathesis of pyridines by a transient Ti[triple bond]C linkage
Brad C Bailey1, Hongjun Fan, John C Huffman
1Department of Chemistry, Molecular Structure Center and School of Informatics, Indiana University, Bloomington, IN 47405, USA.
Abstract:
The transient titanium alkylidyne complex (PNP)TiCtBu (PNP = N[2-P(CHMe2)2-4-methylphenyl]2-), prepared from alpha-hydrogen abstraction of the corresponding alkylidene-alkyl species (PNP)Ti=CHtBu(CH2tBu), can readily cleave the C-N bond of N-heterocycles such as pyridine and 4-picoline at room temperature to afford azametallabicyclic systems. Experimental and theoretical studies strongly favor a ring-opening metathesis pathway where [2 + 2] cycloaddition of pyridine across the TiC linkage ultimately leads to C-N bond rupture.
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