Rerf-Butyl acetate

With most of the R groups, the above reactions can be pushed to completion if the liberated isopropanol or acetate is removed azeotropically with a solvent such as benzene or cyclohexane. Alternatively, the reactions lead to the isolation of mixed alkoxides, many of which can be distilled without apparent disproportionation (6). For the replacement of isopropoxide by rcrr-butoxide groups, transesterification with rerf-butyl acetate is generally preferred (6) because of a larger difference in the boiling points of ferf-butyl and isopropyl acetate. 

Allyl trifluoro acetate cw-4-Decanol Pentafluoropentanoic acid 6,6-Dimethylfulvine Methyl 4-methylbenzoate cyc/oPropanecarboxlic acid cyc/oButane carboxylic acid rerf-Butyl acetic acid... 

Yamamoto has recently described a novel catalytic, asymmetric aldol addition reaction of enol stannanes 19 and 21 with aldehydes (Eqs. 8B2.6 and 8B2.7) [14]. The stannyl ketones are prepared solvent-free by treatment of the corresponding enol acetates with tributyltin methoxide. Although, in general, these enolates are known to exist as mixtures of C- and 0-bound tautomers, it is reported that the mixture may be utilized in the catalytic process. The complexes Yamamoto utilized in this unprecedented process are noteworthy in their novelty as catalysts for catalytic C-C bond-forming reactions. The active complex is generated upon treatment of Ag(OTf) with (R)-BINAP in THF. Under optimal conditions, 10 mol % catalyst 20 effects the addition of enol stannanes with benzaldehyde, hydrocinnamaldehyde, or cinnamaldehyde to give the adducts of acetone, rerf-butyl methyl ketone (pinacolone), and acetophenone in good yields and 41-95% ee (Table 8B2.3). 

Vinyl acetate Vinyl rerf-butyl sulfide 13 0.07 598... 

Fractional distillation of the more volatile este CH3COOR in Eq. (5.15) is required to complete the reaction. Transestoification reactions have been used for the preparation of alkoxides of various metals including Zr, Ti, Ta, Nb, Al, La, Fe, Ga, and V. For example, zirconium rerf-butoxide has been prepared from the reaction between zirconium isopropoxide and terf-butyl ester followed by distillation of isopropyl acetate ... 

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