Cyclopentadienyls reaction with alcohols

C and melts at 173°C. It is iasoluble ia water but dissolves ia alcohols, ether, and benzene. Ferrocene can be prepared by numerous methods, including the reaction of cyclopentadienyl anion, with anhydrous FeCl2. Its extensive reaction chemistry is notable for the aromaticity of the... 

S)-Chloronitroso(2-methyl-2-propenyl) [(7 ,S,S)-neomenthyl]cyclopentadienyl molyb-denum (1) yields on reaction with benzaldehydc the corresponding homoallylic alcohol with > 98% ee1. 

A. G. (1980) Cyclopentadienyl-ruthenium and -osmium chemistry X. Reactions of vinylidene complexes with alcohols and water synthesis of alkoxy (alkyl) carbene, aryl and alkyl complexes. Australian Journal of Chemistry, 33, 1471-1483 (c) Bruce, M.I., Swincer, A.G., Thompson,... 

There are other organometallic derivatives that give Wittig-type olefination reactions, with titanium derivatives being the most commonly used. The initial addition reaction to the carbonyl gives a transient metal-ated alcohol that leads to an alkene. An example is the Tebbe reagent, which exists as a bridged methylene species (see 683), where Cp is cyclopentadienyl. 9 The aluminum species can be varied to include chloride... 

The cyclobutadienepalladium complexes (XXXVI) react with alcohols, usually in the presence of weak bases, to give cyclobutenylpalladium complexes (LXXXIV) isomeric with (XXXV) (see Section VI, F) these reactions are reversed on treatment of (LXXXIV) with hydrogen halides and constitute another preparation of the cyclobutadienepalladium complexes. A related reaction on (w-cyclopentadienyl)(7r-alkoxytetraphenyl-cyclobutenyl)palladium and -nickel complexes (XLIV) (64, 65) is also discussed in Section VI, F. The mechanism of this reaction is not established, but the initial step is probably protonation of the ether. 

Kitazume and Ishikawa have published a number of communications on the regiospecific zinc mediated perfluoroalkylation of a variety of substrates [148-151]. A compilation of these results appeared in 1985 [152] (Scheme 71). Secondary alcohols are available in moderate yield by reaction of perfluoro-alkyl halides (RpX) with aldehydes as the result of a modified Barbier-type reaction [148-152]. However, reaction with ketones gave low yields of the expected tertiary alcohols, although the yields could be doubled by reaction in the presence of a bis[7i-cyclopentadienyl]titanium(II) catalyst, which was prepared in situ by reduction of the dichloride with zinc in the presence of ultrasound. 

Good -selectivity (a as high as 1 16) was found on reaction of 4-Q-acetyl-6-deoxy-2,3-di-Q-methyl-/9-D-allopyranosyl fluoride (D-mycinosyl fluoride) with alcohols in the presence of silver perchlorate and bis(cyclopentadienyl)zirconium dichloride in benzene,and in related fashion a desosamine fluoride has been used to produce -glycosides under mild conditions involving a hafnium complex and the methods have been combined in a total synthesis of the macrocyclic glycoside mycinamycin IV. 

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