ISSN:
0009-2940
Keywords:
Carbonylolefination
;
μ-Methylene complexes
;
Molybdenum reagent
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Organomolybdenum and Organotungsten Reagents, III. - Selective, Nonbasic Carbonylmethylenation Reagents from MoOCl3(THF)2 and MoOCl4: Formation, Thermolability, StructureFrom the family of more than 20 carbonylolefinating μ-methylene molybdenum and tungsten complexes[1,2] the reagent “3”, obtained in solution by treatment of MoOCl3(THF)2 with two equivalents of methyllithium, is probably the most favorable one for chemoselective carbonylolefination reactions. As judged by the 13C- and 1H-NMR spectra the reagent is not a single species, but a mixture of either isomeric 1,3-dioxo-1,3-dimolybda(V)cyclobutane complexes 3, differing in the position of the ligands Cl, O, and THF at the molybdenum atoms, or of oligomers of 3. - Treatment of MoOCl4 with two equivalents of methyllithium gave a carbonylolefinating reagent “4” which, according to NMR data, consists of isomeric or oligomeric 1,3-dioxo-1,3-dimolybda(VI)cyclobutane complexes 4. Both reagents are labile at room temperature, but differ from the classical carbonylolefinating reagents by an acidic rather than a basic character, resistance to hydroxy groups, and high selectivity.
Additional Material:
3 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19931260114
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