Quinine reaction with

The cycloaddition of aldehydes and ketones with ketene under the influence of quinine or quinidine produce chiral 2-oxetanones [46,47]. Solvolytic cleavage of the oxetanone, derived from chloral, and further solvolysis of the trichloromethyl group leads to (5)- and (R)-malic acids with a 98% ee [46] (the chirality of the product depends on the configuration of the catalyst at C-8 and, unlike other alkaloid-induced reactions, it is apparently independent of the presence of the hydroxyl group). No attempts have been made to catalyse the reaction with chiral ammonium salts. 

Use of 2-formylquinuclidine (75) in reactions with organomagnesium compounds led to a new method for the synthesis of quinuclid-2-ylcarbinols (94), which are quinine analogs.145... 

A F,0-bonded Ge" complex is obtained when GeF2 is oxidized by reaction with quinines (equation 32). 

In 2006, Deng and coworkers reported that quinine/quinidine-derived catalysts (64a,b) bearing a free OH group at the C6 -position and bulky phenanthryl moiety at the 9( Opposition quite efficiently promoted the Michael addition of the a-substituted P-ketoesters 65 to the a,P-unsaturated ketones 66 (Scheme 9.21) [18]. The reaction with as little as 1.0mol% of catalyst 64 afforded excellent stereoselectivity and chemical yields (up to 98% ee with quantitative yield) for a wide range of both donors and acceptors. 

O-tert-Butylcarbamoylquinine (t-BuCQN) and 2,6-diisopropylphenylcarbamoyl-quinine (DIPPCQN) type CSPs have been evaluated for the enantiomer separation of a set of isoindolin-l-one fluorescent derivatives of a-amino adds obtained by their reaction with the ortho-phthalaldehydc, naphthalene-2,3-dicarboxaldehyde, or anthracene-2,3-dicarboxaldehyde. The latter reagent afforded the derivatives of the... 

Reaction with trichloroacetone is similarly high-yielding and enantioselective giving the p-lactone 172 and after hydrolysis with inversion, (.S )-citramalic acid 173. Again, quinine gives the other enantiomer. 

A chemical reaction is carried out between the racemate and an optically active form (either laevo-or dextro-) of a substance capable of reacting with the racemate. This other optically active compound is usually derived from a natural source. To resolve the racemates of amines (or other bases) and alcohols, for example, use may be made of the naturally occurring d-tartaric acid (from wine tartar). The reaction with amines gives salts and esters are formed with alcohols. For the resolution of racemates of acids, use is frequently made of alkaloids such as quinine or stiychnine extracted from plants in which each of these alkaloids is present in an optically active form. The racemate mixture forms two diastereoisomers (compounds that are stereoisomers of each other, but are not enantiomers) of a derivative, with the optically active reagent used. If the... 

The naturally occurring (-i-)-calanolide A 21, R = n-Pr, and (H-)-inophyllum B 21, R = Ph, are of interest in that the molecules possess chromene, coumarin and chromanol systems. Total syntheses of them start from a coumarin and generate the chromanone unit through an intramolecular Michael addition which under (-)-quinine catalysis affords cis and trans benzodipyrans with 97% and 52% ee, respectively. The chromene moiety is constructed using the phenylboronic acid assisted reaction with senecioaldehyde. Reduction of the chromanone to the chromanol completes the sequence <04JOC2760>. 

Hofmann appointed the seventeen-year-old Perkin as his personal assistant and guided him to work on the synthesis of the antimalarial drug quinine. Perkin had his own ideas for the synthesis of quinine and pursued them in his lab at his parents home. During Easter break 1856 Perkin ran a reaction with aniline (a compound derived from coal tar) and potassium dichromate that produced a black sludge. Dissolving the sludge in ethyl alcohol, Perkin found that the solution took on an intense purple color. Instead of synthesizing quinine, Perkin had made the first synthetic dye derived from coal tar mauve. 

Syntheses of quinine, quinidine, and their dihydro-analogues also make use of 6-methoxy-4-quinolyl-lithium, this time in reaction with an aldehyde, e.g. 

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