Trifluoromethyl 3-amino alcohol synthesis

Table 6.2. Variation of the amines in the 1,3-amino alcohol synthesis by using 4-trifluoromethyl-benzal-dehyde as constant building block...

Bravo and co-workers report asymmetric syntheses of fluoroalkylamino compoimds via chiral sulfoxides and the stereoselective synthesis of p-fluoroalkyl-p-amino alcohol units using chiral sulfoxides and the Evans aldol reaction. Begde and colleagues discuss the stereoselective and enantioselective synthesis of trifluoromethyl amino alcohols and fluoroalkyl isoserinates. Hoffman reports the aysmmetric fluorination of a-aminoketones, while... 

The Henry nitro-aldol condensation involves the use of P-amino alcohols as the building blocks of fluoromethyl ketones. Although this method has been used extensively in the synthesis of monofluoropeptides (Table 2),19-121 it is more widely utilized as a method for synthesizing trifluoromethyl ketones and the details of the reaction will be discussed in Section 15.1.4.3.2. 

Huguenot, F. and Brigaud, T. (2006) Concise synthesis of enantiopure a-trifluoromethyl alanines, diamines, and amino alcohols via the Strecker-type reaction.. /. Org. Chem., 71, 7075-7078. 

Nitrogen Source Synthesis of Amines. KHMDS has been exploited as a nitrogen source in a few systems. For instance, the ring opening of (trifluoromethyl)oxirane with KHMDS, followed by acidic hydrolysis produced the desired amino alcohol in 61% yield without any variation in the enantiomeric purity (eq 25). ... 

Soc 75 4090 1953, Beilstein 1 II 111, 1 III 2745, 1 IV 3214.] Trifluoioacetone has been used to prepare trifluoromethylimines of chiral amines in order to prepare R or S enantiopure a-trifluoromethyl alanines, diamines and amino alcohols via a Strecker-type synthesis in a few steps [Huguenot Brigand J Org Chem 71 7075 2006. It has also been used to synthesise 2-trifluon)metltyl-7-azaindoles from 2,6-dihalopyridines [Schirok et al. Synthesis 251 2007],... 

Pedrosa R, Sayalero S, Vicente M, Maestro A. An efficient synthesis of enantiomerically enriched trifluoromethylated 1,2-diols and 1,2-amino alcohols with quaternary stereocenters by diastereoselective addition of TMSCF3 to chiral 2-acyl-l,3-perhydrobenzoxazines. J. Org. Chem. 2006 71 2177-2180. 

We developed a new easy and versatile diastereoselective synthesis of these amino alcohols. Our synthetic plan was based on the ring opening of trifluoromethyl epoxy ethers 3, which are easily available in two steps from the cheap ethyl trifluoroacetate, and are useful building blocks. The first step, the Wittig olefination of this ester, is possible because of the increased electrophilicity of the ester carbonyl by the fluorinated moiety (Scheme... 

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