Research Abstract |
The title subjects have been studied with the intention of developing new synthetic reactions by utilizing characteristic chemical properties of newly synthesized complexes. The special emphasis has been placed on the chemistry of eta^3-allylnitrosyliron complexes. The major outcomes of this research can be summarized as follows : 1. (eta^3-Allyl)Fe(CO)_2NO complexes 1 can be synthesized efficiently from allylic halides, (eta^3-1-trimethylsiloxyallyl)Fe(CO)_2NO complexes 2 from alpha, beta-unsaturated carbonyl compounds, (eta^3-2-trimethylsiloxyallyl)Fe(CO)_2NO complexes 3 from alpha-halocarbonyl compounds, [eta^3-1-(acylmethyl)-allyl]Fe(CO)_2NO complexes 4 from 1, 3-dienes, and (eta^3-1-acetoxyallyl)Fe(CO)_2NO complexes 5 from alkenyloxiranes by using Bu_4N^+[Fe(CO)_3NO]^- as a reagent. 2. All these complexes react with both of carbon electrophiles and carbon nucleophiles with a high regio-selectivity. 3. These complexes exhibit interesting reactivity features. The detailed studies have shown that the complexes 1 can be utilized as synthetically equivalent synthons for both of allylcations and allylanions, the complexes 2 as those for both of beta-acylcarbocations and beta-acylcarbanions, the complexes 3 as those for both of alpha-acylcarbocations and alpha-acylcarbanions, the complexes 4 as intermediates for 1, 4-functionalization of 1, 3-dienes, and the complexes 5 as intermediates for the synthesis of multifunctionalized alcohols. 4. The allylic ligands of 1, 2, 3, and 4 undergo a conjugate addition to alpha, beta-unsaturated carbonyl compounds, affording a variety of multifunctionalized compounds with a high selectivity. 5. The reactions of the iron complexes with carbon electrophiles and carbon nucleophiles proceed via two different, distinctive stereochemical courses, and the regio- and stereo-selectivities of both the reactions are generally high.
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