低対称コバルト(III)錯体の低温における偏光スペクトル測定

金沢大学理学部研究課題/領域番号:X00210----474266研究期間(年度):1979出典：「低対称コバルト(III)錯体の低温における偏光スペクトル測定」研究成果報告書　課題番号X00210----474266（KAKEN：科学研究費助成事業データベース（国立情報学研究所）） （https://kaken.nii.ac.jp/ja/grant/KAKENHI-PROJECT-X00210----474266/）を加工して作

Catalytic asymmetric dialkynylation reaction of α-dinitrone by utilizing tartaric acid ester as a chiral auxiliary

金沢大学理工研究域物質化学系The asymmetric addition of alkynylzinc reagents, prepared in situ from dimethylzinc and 1-alkynes, to α-dinitrones derived from glyoxal and N-(4-isopropylbenzyl)hydroxylamine was investigated by utilizing dicyclohexyl (R,R)-tartrate as a chiral auxiliary. The addition reaction of methyl(2-phenylethynyl)zinc afforded the corresponding optically active C2-symmetric (R,R)-bis(hydroxylamine) derivative with enantioselectivities of 90% and 81% ee by utilizing a stoichiometric and catalytic amount of the tartrate, respectively. Furthermore, the catalytic addition reaction of several alkynylzinc reagents also furnished the corresponding bis(hydroxylamine) with moderate to good enantioselectivities. © 2008 Elsevier Ltd. All rights reserved

Trans,trans,trans-Diethanoldiquinaldinatoiron(II)

金沢大学理学部金沢大学大学院自然科学研究科物質創成The title complex, trans,trans,trans-[FeII(C10H 6NO2)2-(C2H6O) 2], is centrosymmetric and the quinaldinate ligands form five-membered chelate rings. The geometry of the complex is distorted octahedral, with a trans-FeN2O4 chromophore. The hydroxy H atom forms an intermolecular hydrogen bond with the carbonyl O atom of the quinaldinate ligand. © 2003 International Union of Crystallography Printed in Great Britain - all rights reserved

Stereoselective hetero Diels-Alder reaction of selenoaldehydes with pentavalent phosphole chalcogenides

金沢大学大学院自然科学研究科物質創成金沢大学工学部Stereoselective hetero Diels-Alder reaction of selenoaldehydes, generated by thermal retro Diels-Alder reaction of anthracene cycloadducts, with pentavalent 3,4-dimethylphosphole chalcogenides at 110 °C in toluene to give the corresponding [4+2] cycloadducts as a single diastereoisomer in good yields, accompanied by a slight scrambling of chalcogen atoms. Higher reaction temperature led to an increase of the scrambling between chalcogen atoms. © 2007 Elsevier Ltd. All rights reserved

Oxidation of pyrrole-2-carboxylates with o-chloranil and its synthetic application

金沢大学理工研究域物質化学系t-Butyl 3,4-dialkyl-1H-pyrrole-2-carboxylates were oxidized with ochloranil in the presence of MeOH to afford the corresponding 5-methoxypyrrolin-2-one derivatives. The resulting 5-methoxypyrrolin-2-one was reacted with various nucleophiles under acidic conditions to afford the functionalized pyrrolinone derivatives in good yields. © The Japan Institute of Heterocyclic Chemistry

Crystal structures of racemic and enantiomeric 5-isopropyl-5-methylhydantoin

Crystal structures of racemic and enantiomeric 5-isopropyl-5-methylhydantoin (IPrMH) have been determined by single crystal X-ray diffraction. Melting temperatures and solid state infrared spectra are also measured. Racemic IPrMH has a lower melting temperature than the pure enantiomer by 25 °C. The infrared spectrum of racemic IPrMH is identical with that of the pure enantiomer. Nevertheless, the racemic IPrMH doesn’t crystallize as a conglomerate but as a racemic compound. The racemic and the enantiomeric crystals are very similar to each other in molecular geometries and intermolecular interactions. In the both cases, the molecules are connected via N−H···O hydrogen bonds to form R22(8) rings, and these rings are linked into infinite one-dimensional tapes. In the racemic crystal, a single tape is composed of single enantiomer and itself is homochiral

Magnesium-tartramide complex mediated asymmetric Strecker-type reaction of nitrones using cyanohydrin

An asymmetric Strecker-type reaction of nitrones using acetone cyanohydrin as a source of HCN has been realized. A magnesium-tartramide complex, generated from (R,R)-2,3-dihydroxy-1,4-di(pyrrolidin-1-yl)-butane-1,4-dione and MeMgBr, promoted transcyanation from the bromomagnesium salt of the cyanohydrin, in the presence of a catalytic amount of DBU, to afford the corresponding optically active (S)-α-amino nitrile derivatives. The reaction was applicable to various nitrones giving high-to-excellent enantioselectivities. © 2013 American Chemical Society

One-pot stereoselective synthesis of 2-acylaziridines and 2-acylpyrrolidines from N-(propargylic)hydroxylamines

The stereoselective direct transformation of N-(propargylic)hydroxylamines into cis-2-acylaziridines was achieved by the combined use of AgBF4 and CuCl. Copper salts were found to promote the transformation of the intermediary 4-isoxazolines into 2-acylaziridines and both 3-aryl- and 3-alkyl-substituted 2-acylaziridines could be prepared by using this method. Furthermore, subsequent 1,3-dipolar cycloaddition of azomethine ylides that were generated in situ from the intermediary 2-acylaziridines with maleimides was achieved in a stereoselective one-pot procedure to afford the corresponding 2-acylpyrrolidines, which consisted of an octahydropyrrolo[3,4-c]pyrrole skeleton. Love the way ylide: The transformation of N-(propargylic) hydroxylamines into cis-2-acylaziridines and subsequent 1,3-dipolar cycloaddition of the in situ generated azomethine ylides with maleimides stereoselectively afforded 2-acylpyrrolidines. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim