Format

Send to

Choose Destination
Chemistry. 2012 Nov 19;18(47):15079-85. doi: 10.1002/chem.201202796. Epub 2012 Oct 11.

M4(CH2)4 cubane-type rare-earth methylidene complexes: unique reactivity toward unsaturated C-O, C-N, and C-S bonds.

Author information

1
State Key Laboratory of Fine Chemicals, Department of Polymer Science and Engineering, School of Chemical Engineering, Dalian University of Technology, Dalian, Liaoning 116024, PR China.

Abstract

The reactivity of the cubane-type rare-earth methylidene complex [Cp'Lu(μ(3)-CH(2))](4) (1, Cp' = C(5)Me(4)SiMe(3)) with various unsaturated electrophiles was investigated. The reaction of 1 with CO (1 atm) at room temperature gave the bis(ketene dianion)/dimethylidene complex [Cp'(4)Lu(4)(μ(3)-CH(2))(2)(μ(3),η(2)-O-C=CH(2))(2)] (2) in 86 % yield through the insertion of two molecules of CO into two of the four lutetium-methylidene units. In the reaction with the sterically demanding N,N-diisopropylcarbodiimide at 60 °C, only one of the four methylidene units in 1 reacted with one molecule of the carbodiimide substrate to give the mono(ethylene diamido)/trimethylidene complex [Cp'(4)Lu(4)(μ(3)-CH(2))(3) {iPrNC(=CH(2))NiPr}] (3) in 83% yield. Similarly, the reaction of 1 with phenyl isothiocyanate gave the ethylene amido thiolate/trimethylidene complex [Cp'(4)Lu(4)(μ(3)-CH(2))(3) {PhNC(S)=CH(2)}] (4). In the case of phenyl isocyanate, two of the four methylidene units in 1 reacted with four molecules of the substrate at ambient temperature to give the malonodiimidate/dimethylidene complex [Cp'(4)Lu(4)(μ(3)-CH(2))(2) {PhN=C(O)CH(2)(O)C=NPh}(2)] (5) in 87% yield. In this reaction, each of the two lutetium-methylidene bonds per methylidene unit inserted one molecule of phenyl isocyanate. All the products have been fully characterized by NMR spectroscopy, X-ray diffraction, and microelemental analyses.

PMID:
23059833
DOI:
10.1002/chem.201202796

Supplemental Content

Loading ...
Support Center