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Molecules bearing aryl- and trifluoromethyl- substituted tertiary alcohol moieties are important as bioactive molecules, enantiomer-discriminating reagents, and their synthons and building blocks. To concisely synthesize these molecules, we have developed aldol reactions of ketone donors with aryl trifluoromethyl ketone acceptors catalyzed by 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU). The reactions were relatively fast, and the products were obtained in good to high yields under mild conditions. The C¢C bonds of the aldol reactions formed in perfect regioselectivities at the methyl group of the alkyl methyl ketones, at the γ-position of the β-keto esters, and at the methyl group of the β-methyl-substituted cyclic enones. For the aldol products from the reactions of β-keto esters, the enantiomerically pure forms were obtained by resolution of the enamines of the aldol products with a homochiral amine. Our methods provide a concise, fast access to molecules with tetrasubstituted carbon centers with trifluoromethyl-substituted alcohol moieties. [ABSTRACT FROM AUTHOR]

Different types of reactants are investigated to produce the desired target compounds. [ABSTRACT FROM AUTHOR]

Molecules with furanose units are often bioactive. To concisely synthesize these molecules, we have developed aldol reactions of 1,2-diketones that afford furanose derivatives in one pot. For these reactions with the use of N , N ′-diisopropylethylamine as catalyst, aldol products were obtained via C–C bond formation at the internal methylene carbon of the acetyl alkyl ketone derivatives. Regioselectivities of the reactions depended on the catalyst. The aldol products from the reactions with aldehydes in which the C–C bond formation occurred at the internal methylene carbon of the acetyl alkyl ketone derivatives were easily air-oxidized to afford the corresponding 2-hydroxy-2 H -furanone derivatives. [ABSTRACT FROM AUTHOR]