Formation of substituted ferracyclopentadiene complexes by the reaction of alkynes with protonated diferra-{mu}-azaallylidene complexes
- Pennsylvania State Univ., University Park, PA (United States); and others
The dinuclear complexes [Fe{sub 2}({mu}-C(H)(CH=NHR{prime}))(CO){sub 8}][BF{sub 4}](R{prime} = Bu{sup t},Ph), which possess protonated {mu}{sub 2}, {eta}{sup 1}-azaallylidene ligands and are derivatives of the parent methylene complex Fe{sub 2}({mu}-CH{sub 2})(CO){sub 8}, react with alkynes (R{sup 1}C{triple_bond}CR{sup 2}) to give isomeric hydroxy-imino-ferracyclopentadiene complexes, Fe{sub 2}({mu}-CR{sup 1}CR{sup 2}C(OH)C(C(H)=NR{prime})))(CO){sub 6}, and amino-ferracyclopentadiene complexes, Fe{sub 2}({mu}-CR{sup 1}CR{sup 2}CHC(N-(H)R{prime}))(CO){sub 6}, with the distribution of products dependent on the alkyne employed. The former were also isolated as their BF{sub 3} adducts Fe{sub 2}({mu}-CR{sup 1}CR{sup 2}C(O-BF{sub 3})C(C(H)=NHR{prime})(CO){sub 6}, and two of these latter complexes have been crystallographically characterized. They have a typical ferracyclopentadiene (ferrole) ring with an iminium substituent (C(H)=NHR{prime}) on the {alpha}-carbon of the ring, which is hydrogen-bonded though the nitrogen atom to the oxygen substituent on the {beta}-carbon of the ferracyclopentadiene ring, which is in turn coordinated by the BF{sub 3} group. The BF{sub 3} group can be removed by reaction with aqueous base to give the free hydroxy-imino-ferracyclopentadiene complexes. The amino-ferracyclopentadiene complex with R{prime}=Bu{sup t} and R{sup 1} = R{sup 2} = Ph has also been crystallographically characterized. It is a typical ferracyclopentadiene complex with an amino group on the {alpha}-carbon. The amino-ferracyclopentadiene complexes are also formed in near quantitative yield by an acid-catalyzed ring contraction of the 2-ferrapyridine complexes Fe{sub 2} ({mu}-CR{sup 1}CR{sup 2}CHCHNR{prime})(CO){sub 6}. 20 refs., 3 figs., 7 tabs.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 567347
- Journal Information:
- Organometallics, Journal Name: Organometallics Journal Issue: 7 Vol. 11; ISSN ORGND7; ISSN 0276-7333
- Country of Publication:
- United States
- Language:
- English
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