139758-92-2Relevant academic research and scientific papers
Organic Syntheses via Transition Metal Complexes, 59. - Cyclobutanimines from Carbenechromium or -tungsten Complexes, Isocyanides, and Alkenes by -Cycloaddition Reactions of Ketenimine Complexes; Ligand Disengagement with Pyridine
Aumann, Rudolf,Krueger, Carl,Goddard, Richard
, p. 1627 - 1634 (2007/10/02)
10-Iminotricyclo2,9>deca-3,5-diene complexes syn/anti-4 are obtained in yields higher than 90percent by the addition of isocyanides RNC 2 a), CH3 (b)> to (cycloheptatrien-1-ylmethyl)carbene complexes LnM=C(OEt)CH2(C7H7) 1 a), W(CO)5 (b)>.The reactions involve an intermediate formation of ketenimine complexes LnM 3 by the insertion of 2 into the M=C bonds of 1.Complexes 3 isomerize to give the cyclobutanimines 4 by an intramolecular s + 2a>-cycloaddition reaction of the ketenimine to the alkene unit.The structure of anti-4c has been determined by a crystal structure analysis.Complexes 4 react with pyridine by the fragmentation of the four-membered ring to yield a tetrahydroazulen-1-imine 6 which was hydrolyzed to the corresponding ketone 7; 7 is also obtained along an independent route by the photolysis of 1a in the presence of carbon monoxide.The first isolated product of the latter reaction is the tricyclo2,9>deca-3,5-dienone 9, which presumably is formed via an intermediate ketene complex N and the tricyclic ketone O; 9 on warming with pyridine rearranges to 7. Key Words: Cyclobutanimines via carbene complexes / 10-Iminotricyclo2,9>deca-3,5-dienes / (Cyloheptatriene-1-ylmethyl)carbene complexes of chromium and tungsten / Ketenimine complexes, cycloadditions with alkenes / Keten complexes, cycloadditions
