Ferrocene, acetyl

Acetylferrocene Highly Toxic Ferrocene, acetyl-(9) (1271-55-2) N,N-Dimethyl1ormamide Cancer Suspect Agent Formamide, N,N-dimethyl-(8,9) (68-12-2)... 

SYNS ACETYLFERROCENE 1-ACETYLFERROCENE FERROCENE, ACETYL- MONACETYLFERROCENE... 

FERRIC SULFATE see FBAOOO FERRICYTOCHROME C see CQM325 FERRIDEXTRAN see IGSOOO FERRIVENTN see IHGOOO FERROANTHOPHYLLITE see ARM264 FERROCENE see FBCOOO FERROCENE, ACETYL- see ABA750 FERROCENE, 1,1 -... 

Langmuir et al. studied the stabilization of n-GaAs photo-anodes by some redox couples (Br /Br", Ij /I", and ferrocene, acetyl ferrocene, N,N -tetramethyl-p-... 

A mixture of ferrocene, acetyl chloride, and molybdenum hexacarbonyl in n-hep-tane stirred and refluxed 1-2 days under Ng -> acetylferrocene. Y 76%. F. e. s. H. Alper and S. M. Kempner, J. Org. Chem. 39, 2303 (1974) Friedel-Crafts syntheses catalyzed by poly sty renetricar bony Imolybdenum s. C. P. Tsonis and M. F. Farona, J. Organometal. Chem. 114, 293 (1976). 

Friedel-Crafts acylation involves electrophilic attack by acyl cation (CHsCO ) on the ring, and the ring s electronic character should indicate its susceptibility to attack. Compare electrostatic potential maps of ferrocene and acetylferrocene. Which molecule contains the most electron-rich ring Which acylation reaction should be faster Does an acetyl substituent enhance or diminish ring reactivity What should be the major product when ferrocene is combined with one equivalent of acetic anhydride ... 

Attempted acetylation of 2,2, 5,5 -tetramethyl-l,l -distibaferrocene (29) or 3,3, 4,4 -tetramethyl-l,T-distibaferrocene (61) led to destruction of the ring system and the formation of intractable products. Acid-catalyzed H/D isotopic exchange (Scheme 14) is the simplest electrophilic aromatic substitution. Both l,T-diphosphaferrocene55 (7) and l,l -diarsa-ferrocene (8)13 undergo rapid exchange at the a positions when treated... 

The ferrocene analog 65 is reported to give a 20% yield of the 2-acetyl derivative 82 when treated with MeCOCl/AlCl3 (Scheme 14) (58). How-... 

Fatty acids PRE-CD with 3-bromo-acetyl-1,1 -di-methyl ferrocene +0.6 250... 

Solid or liquid organometallic compounds such as ferrocene and its various derivatives, iron (III) acetyl acetonate, metal chelates etc. 

The major product is the heteroannular disubstituted derivative, l,l -diacetyl-ferrocene (I), while a very small amount of a homoannular isomer, 1,2-diacetylfer-rocene (II), is also obtained. The first acetyl group therefore appears to deactivate the substituted ring toward further electrophilic substitution, and the second acetyl group preferentially enters the opposite ring. 

The exceedingly high reactivity of ferrocene to Friedel-Crafts acylation is exemplified by the fact that mild catalysts such as stannic chloride (63), boron trifluoride (32), zinc chloride (86), and phosphoric acid (29), can be used with considerable success. When ferrocene and anisole were allowed to compete for limited amounts of acetyl chloride and aluminum chloride, acetylferrocene was the sole product isolated, again illustrating the high reactivity of ferrocene toward electrophilic reagents (6). 

While metallocenes are usually acetylated with acid halides, acid anhydrides, or carboxylic acids, a number of other acylating agents have been reported. The reaction of ferrocene with various isocyanates and aluminum chlorides leads to N-substituted ferrocenecarboxamides (IX) (89). Use of ruthenocene in place of ferrocene leads to analogous results (88). The preparation of V-phenyl-ferrocenecarboxamide from phenyl isocyanate in this manner has been used as a proof of structure for the product obtained from the Beckmann rearrangement of benzoylferrocene oxime (124). 

PFeOC24H21, Ferrocene, [(diphenylphosphino) acetyl]-, [125798-01-8], 31 141 PGaClgH36, Gallium, trihydro(tricyclohexyl-phosphine)-, (T-4)-, [141727-22-2], 31 79 PI07ReC7H, Rhenium, tetracarbonyliodo (trimethyl phosphite-P)-, (OC-6-33)-, [134770-89-1], 31 249 PN02C24H42, Acetamide, Al,/V-bis(2-methyl-propyl>-2-(octylphenylphosphinyl)-, [83242-95-9], 31 145... 

Light is switched off at +0.5 V vs. SCE for the cathodic sweep. In (a) there is no added reductant (b), (c), and (d) contain 0.5mM ferrocene, 1, l -dimethylferrocene, and acetyl-ferrocene, respectively. Acetylferrocene does not attenuate the surface ferricenium surface ferrocene wave since it is not a sufficiently powerful reductant. Ferrocene and 1, l -dimelhylferrocene both attenuate the surface ferricenium - surface ferrocene wave. But l,l -dimethylferrocene is more effective under identical conditions despite the fact that the same, mass transport-limited, steady-state photocurrent is found for these two reductants. These data suggest that after the light is switched off the reduction of surface ferricenium is controlled partially by mass transport and partly by the electron transfer rate (see text). 

The former is prepared (Expt 6.15) by the reaction of cyclopentadiene with iron(n) chloride in the presence of diethylamine. Iron(n) chloride is prepared in situ from iron(m) chloride in tetrahydrofuran by reduction with iron metal. This preparation is one of the simplest for ferrocene, although not of general application for substituted ferrocenes. The acetylation of ferrocene in a Friedel-Crafts manner to yield the monoacetyl derivative is described in Expt 6.122. 

The editors are grateful to Dr R. Thomas, School of Chemistry, Thames Polytechnic, for the experimental details of the acetylation of ferrocene. 

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