A practical and convenient method for the efficient and regio- and stereoselective ring-opening of enantiopure monosubstituted epoxides by sodium azide under hydrolytic conditions is reported. The ring-opening of enantiopure styryl and pyridyl (S)-epoxides by N3− in hot water takes place preferentially at the internal position with complete inversion of configuration to produce (R)-2-azido ethanols with up to 99% enantio- and regioselectivity, while the (S)-adamantyl oxirane provides mainly the (S)-1-adamantyl-2-azido ethanol in excellent yield. In general, 1,2-amino ethanols were obtained in high yield and excellent enantiopurity by the reduction of the chiral 1,2-azido ethanols with PPh3 in water/THF, and then converted into the Boc or acetamide derivatives.(R)-2-Azido-2-phenylethanolC8H9N3Oee = 99%[α]D22 = −268 (c 0.7, CHCl3)Source of chirality: Asymmetric synthesisAbsolute configuration: (R)(R) Azido-2-(4-chlorophenyl)ethanolC8H8N3OClee = 98%[α]D22 = −151 (c 1.0, CHCl3)Source of chirality: Asymmetric synthesisAbsolute configuration: (R)(R)-2-Azido-2-(4-nitrophenyl)ethanolC8H8N4O3ee = 73%[α]D22 = −111 (c 0.6, CHCl3)Source of chirality: Asymmetric synthesisAbsolute configuration: (R)(S)-2-Azido-1-(4-nitrophenyl)ethanolC8H8N4O3ee = 90%[α]D22 = +76 (c 0.22, CHCl3)Source of chirality: Asymmetric synthesisAbsolute configuration: (S)(R)-2-Azido-2-(4-bromophenyl)ethanolC8H8BrN3ee = 97%[α]D22 = −373 (c 0.15, CHCl3)Source of chirality: Asymmetric synthesisAbsolute configuration: (R)(R)-2-Azido-2-(3-bromophenyl)ethanolC8H8BrN3Oee = 99%[α]D22 = −174 (c 0.4, CHCl3)Source of chirality: Asymmetric synthesisAbsolute configuration: (R)(R)-2-Azido-2-(p-tolyl)ethanolC9H11N3Oee = 95%[α]D22 = −190 (c 0.3, CHCl3)Source of chirality: Asymmetric synthesisAbsolute configuration: (R)(R)-2-Azido-2-(3-methoxyphenyl)ethanolC9H11N3O2ee = 99%[α]D22 = −200 (c 0.6, CHCl3)Source of chirality: Asymmetric synthesisAbsolute configuration: (R)(R)-2-Azido-2-(4-fluorophenyl)ethanolC8H8FN3Oee = 99%[α]D22 = −182 (c 0.8, CHCl3)Source of chirality: Asymmetric synthesisAbsolute configuration: (R)(R)-2-Azido-2-(4-methoxyphenyl)ethanolC9H11N3O2ee = 98%[α]D22 = −148 (c 2, MeOH)Source of chirality: Asymmetric synthesisAbsolute configuration: (R)(R)-2-Azido-2-(3-pyridyl)ethanolC7H8N4Oee = 95%[α]D22 = −194 (c 3.2, CHCl3)Source of chirality: Asymmetric synthesisAbsolute configuration: (R)(S)-1-(Adamantan-1-yl)-2-azidoethan-1-olC12H19N3Oee = 99.5%[α]D20 = −18 (c 1.1, MeOH)Source of chirality: Asymmetric synthesisAbsolute configuration: (S)(R)-2-Amino-2-phenylethanolC8H11NOee = 99%[α]D22 = −62 (c 0.2, CHCl3)Source of chirality: Asymmetric synthesisAbsolute configuration: (R)(R)-Amino-2-(4-chlorophenyl)ethanolC8H10ClNOee = 99%[α]D22 = −68 (c 0.2, CHCl3)Source of chirality: Asymmetric synthesisAbsolute configuration: (R)(R)-2-Amino-2-(4-bromophenyl)ethanolC8H10BrNOee = 99%[α]D22 = −62 (c 0.15, CHCl3)Source of chirality: Asymmetric synthesisAbsolute configuration: (R)(R)-2-Amino-2-(3-bromophenyl)ethanolC8H10BrNOee = 99%[α]D22 = −51 (c 0.6, CHCl3)Source of chirality: Asymmetric synthesisAbsolute configuration: (R)(R)-2-Amino-2-(p-tolyl)ethanolC9H13NOee = 99%[α]D22 = −50 (c 0.09, CHCl3)Source of chirality: Asymmetric synthesisAbsolute configuration: (R)(R)-2-Amino-2-(3-methoxyphenyl)ethanolC9H13NO2ee = 99%[α]D22 = −39 (c 0.09, CHCl3)Source of chirality: Asymmetric synthesisAbsolute configuration: (R)(R)-2-Amino-2-(4-fluorophenyl)ethanolC8H10FNOee = 99%[α]D22 = −58 (c 0.3, CHCl3)Source of chirality: Asymmetric synthesisAbsolute configuration: (R)(R)-2-Amino-2-(4-methoxyphenyl)ethanolC9H13NO2ee = 99%[α]D18 = +38 (c 0.43, CHCl3)Source of chirality: Asymmetric synthesisAbsolute configuration: (R)(R)-2-Amino-2-(3-pyridyl)ethanolC7H10N2Oee = 95%[α]D20 = −40 (c 1.0, CHCl3)Source of chirality: Asymmetric synthesisAbsolute configuration: (R)(S)-1-(Adamantan-1-yl)-2-aminoethan-1-olC12H21NOee = 96%[α]D20 = +19 (c 1.1, MeOH)Source of chirality: Asymmetric synthesisAbsolute configuration: (S)

Highly enantiopure (1-aryl)- and (1-naphthyl)-1-ethylamines were synthesized by the borane-mediated reduction of single-isomeric (E)- and (Z)-O-benzyloxime ethers using the stable spiroborate ester derived from (S)-diphenyl valinol and ethylene glycol as the chiral catalyst. Primary (R)-arylethylamines were prepared by the reduction of pure (Z)-ethanone oxime ethers in up to 99% ee using 15% of catalyst. Two convenient and facile approaches to the synthesis of new and known calcimimetic analogues employing enantiopure (1-naphthalen-1-yl)ethylamine as chiral precursor are described.

An asymmetric synthesis for the preparation of nonracemic amines bearing heterocyclic and heteroaromatic rings is described. A variety of important enantiopure thionyl and arylalkyl primary amines were afforded by the borane-mediated enantioselective reduction of O-benzyl ketoximes using 10% of catalyst 10 derived from (S)-diphenylvalinol and ethylene glycol with excellent enantioselectivity, in up to 99% ee. The optimal condition for the first asymmetric reduction of 3- and 4-pyridyl-derived O-benzyl ketoxime ethers was achieved using 30% of catalytic loading in dioxane at 10 °C. (S)-N-ethylnornicotine (3) was also successfully synthesized from the TIPS-protected (S)-2-amino-2-pyridylethanol in 97% ee.