Organolithium with carbonyl compounds

The reactions of organolithium compounds with carbonyl compounds, including carbon dioxide, may be interpreted as follows ... 

Organolithium reagents (Rli) react with carbonyl compounds in the same way as Grignard reagents. 

The competition between insertion and hydrogen transfer is also crucial to the selectivity of the reaction of aluminium alkyls with carbonyl compounds. Aluminium alkyls, like organolithium compounds and Grignard reagents, can add to aldehydes and ketones to form secondary or tertiary alcohols, respectively. If the aluminium alkyl has a j -hydrogen, however, reduction of the carbonyl compound is a common side reaction, and can even become the main reaction [16]. Most authors seem to accept that reduction involves direct j5-hydrogen transfer to ketone. 

Similarities and Differences in the Reactions of Organolithium vs. Grignard Reagents with Carbonyl Compounds... 

In the presence of BF3, even THF can be cleaved to give 8-lithioalkoxide 48,67 and with catalytic naphthalene68 the organolithium can be trapped with carbonyl compounds. Acid-catalysed ring closure generates tetrahydropyrans such as 49 - a convenient ring expansion of THF. 

T.3.3 Correlate reaction the reaction of telluronium salts with carbonyl compounds mediated by organolithium reagents - formation of secondary alcohols... 

In the case of 2,3-benzofuran (55), a stereoselective ring opening lithiation takes place under the same reaction conditions as for 2,3-dihydrobenzofuran (47) shown in Scheme 13, yielding the (Z)-organolithium intermediate (56) which, by reaction with different electrophiles and final acidic hydrolysis, gives the expected (Z)-products (57). The cyclization of the products obtained by reaction of intermediate (56) with carbonyl compounds under acidic conditions, affords the expected substituted 2H-chromenes (58) (Scheme 15) (01EJ02809). 

Heterosubstituted allenes are versatile synthetic intermediates. Direct substitution of a heteroatom on the allene confers upon the system an electronic bias that allows the molecule to be deprotonated easily using an organolithium reagent, and also permits regioselective reaction with carbonyl compounds. 

Reagents of the type (1) can be prepared by the reaction of triphenylvinyl-silane with organolithium compounds. They react with carbonyl compounds to... 

In principle, another general method for the preparation of hydroxyl-functionalized polymers is through the reaction of polymeric organolithium compounds with carbonyl compounds. The reaction of polymeric organolithium compounds with the simplest carbonyl compound, formaldehyde, has been reported. ... 

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