FIELD: organic synthesis. SUBSTANCE: optically active beta-aminoalkixyborane complexes with general formula I: 
(I) are provided, in which formula R1 is C1-C3-alkyl and C7-C11-arylalkyl, R2 is C1-C8-alkyl, C3-C7- cycloalkyl or C7-C11-arylalkyl, or R1 and R2 form (CH2)n in which n=3 or 4 and Ar is naphthyl, anthryl or phenanthryl which can be substituted by 1-3 substituents selected from the group including halogen, C1-C6-alkyl, C6-C10-aryl, and 
-alkoxy. Also provided is optically active beta-aminoalcohol derivatives with general formula II: R1 (II), where R2, R2, n and Ar are the same as defined above on condition that, when Ar is naphthyl, C1-C8 is not R1-alkyl or when Ar is phenanthryl, R2 and (CH2)3 do not form 
. Methods of preparing compounds I, IV, VI-1 and VI-2 [
(IV), 
(VI-1), and 
(VI-2)] are as well provided. Compounds of invention give rise to higher asymmetrical yield and higher diastereoselectivity (higher sin- isomer formation) than standard borane complexes. These compound may also find use in pharmaceutics, in agriculture, or for cosmetics. EFFECT: facilitated asymmetrical syntheses. 7 cl, 2 dwg, 6 tbl, 4 ex
