Faculty Profiles - SAITO, Susumu

Papers - SAITO, Susumu

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Versatile Ruthenium Complex "RuPCY" for Directed Catalytic Hydrogen Management in Organic Synthesis Invited Reviewed

Yuki Takada, Megumi Iida, Kazuki Iida, Takashi Miura, Susumu Saito

JOURNAL OF SYNTHETIC ORGANIC CHEMISTRY JAPAN Vol. 74 ( 11 ) page： 1078 - 1089 2016.11

Language：English Publishing type：Research paper (scientific journal) Publisher：SOC SYNTHETIC ORGANIC CHEM JPN

The ruthenium (Ru) precatalyst complex dichlorobis[2-[(dicyclohexylphosphino-kappa P)methyl]pyridine- kappa N]ruthenium(II) (RuPCY), first developed by us, was shown to be useful not only for the catalytic hydrogenation of inert carboxylic acid derivatives including amides and esters, but also for the catalytic dehydrogenation of primary (1 degrees) and secondary (2 degrees) alcohols and subsequent reactions. RuPCY is versatile, and different Ru catalysts derived therefrom are quite useful for realizing a variety of indiscrete/discrete catalytic hydrogen management (HyMA) reactions. The sequential use of different starting materials and different catalysts (all derived from RuPCY) permits otherwise challenging orthogonal HyMA processes. This accommodates, for example, a salt-free access and/or shortcut to synthetic intermediates of pharmaceutically important substances such as donepezil (Aricept (R)) and atorvastatin (Lipitor (R)).

Web of Science

Synthesis of morphan derivatives with additional substituents in 8-position Reviewed

Janine Stefaowitz, Dirk Schepmann, Constantin Daniliuc, Susumu Saito, Bernhard Wuensch

ZEITSCHRIFT FUR NATURFORSCHUNG SECTION B-A JOURNAL OF CHEMICAL SCIENCES Vol. 71 ( 10 ) page： 1057 - 1069 2016.10

Language：English Publishing type：Research paper (scientific journal) Publisher：WALTER DE GRUYTER GMBH

The morphan system (2-azabicyclo[3.3.1]no-nane) as a substructure of morphine is of major interest in medicinal chemistry. Herein, the synthesis of morphan derivatives with additional substituents at the propano bridge is reported. In order to avoid the isolation of the smelly and volatile nitrile 6 and the very polar primary amine 9, an efficient one-pot, three-step sequential transformation of the mesylate 5 into amides 10 was developed. The key step of the synthesis was the stereoselective intramolecular opening of the epoxides 11a-d leading to the exo-configured 8-hydroxymorphans 12a-d. The configuration of the exo-configured hydroxymorphan 12d bearing the kappa- and sigma-pharmacophoric 3,4-dichlorophenylacetyl moiety was inverted by oxidation and stereoselective reduction. An X-ray crystal structure analysis of the benzamide 12c confirmed the relative configuration of the hydroxymorphans 12a-d and 14d.

DOI： 10.1515/znb-2016-0129

Web of Science

Stereoselective Synthesis of cis,cis-Configured Perhydroquinoxaline-5-Carbonitrile from Cyclohex-2-en-1-ol Reviewed

Adrian Schulte, Susumu Saito, Bernhard Wuensch

JOURNAL OF HETEROCYCLIC CHEMISTRY Vol. 53 ( 2 ) page： 533 - 536 2016.3

Language：English Publishing type：Research paper (scientific journal) Publisher：WILEY-BLACKWELL

cis,cis-Configured perhydroquinoxaline-5-carbonitrile 10 was synthesized stereoselectively by ditosylation of trans,cis-2,3-dihydroxycyclohexane-1-carbonitrile 4 and subsequent reaction with ethylenediamine. The diol precursor 4 was stereoselectively obtained by regioselective opening of the epoxide 3 with KCN in water avoiding hazardous Et2AlCN.

DOI： 10.1002/jhet.2322

Web of Science

N-Methylation of Amines with Methanol at Room Temperature Reviewed

Vasily N. Tsarev, Yuna Morioka, Joaquim Caner, Qing Wang, Richiro Ushimaru, Akihiko Kudo, Hiroshi Naka, Susumu Saito

ORGANIC LETTERS Vol. 17 ( 10 ) page： 2530 - 2533 2015.5

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC

N-Methylation of amines with methanol proceeds at room temperature in the presence of a silver-loaded titanium dioxide (Ag/TiO2) photocatalyst under UV-vis light irradiation. This method allows facile synthesis/isolation of N-methylamines bearing various functional groups including N-benzyl, N-allyl, N-Boc, hydroxyl, ether, acetal, carboxamide, formamide, and olefin groups.

DOI： 10.1021/acs.orglett.5b01063

Web of Science

PubMed

One-step synthesis of patterned polymer brushes by photocatalytic microcontact printing Invited Reviewed

Friederike Kettling, Benjamin Vonhoeren, Jennifer A. Krings, Susumu Saito, Bart Jan Ravoo

CHEMICAL COMMUNICATIONS Vol. 51 ( 6 ) page： 1027 - 1030 2015

Language：English Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY

A novel method to prepare microstructured polymer brushes using TiO2 nanoparticles and photocatalytic microcontact printing is described. It is shown that ethanol amine can be polymerized to linear polyethyleneimine (PEI) driven by the photocatalytic action of TiO2. Upon UV irradiation during microcontact printing of ethanol amine with a stamp coated with TiO2 nanoparticles, patterned polymer brushes with a length of around 50 nm are obtained.

DOI： 10.1039/c4cc08646e

Web of Science

PubMed

Hydration of nitriles to amides by a chitin-supported ruthenium catalyst

Matsuoka Aki, Isogawa Takahiro, Morioka Yuna, Knappett Benjamin R, Wheatley Andrew E. H, Saito Susumu, Naka Hiroshi

RSC ADVANCES Vol. 5 ( 16 ) page： 12152-12160 2015

Bromolactamization: Key Step in the Stereoselective Synthesis of Enantiomerically Pure, cis-Configured Perhydropyrroloquinoxalines Reviewed

Adrian Schulte, Xingci Situ, Susumu Saito, Bernhard Wuensch

CHIRALITY Vol. 26 ( 12 ) page： 793 - 800 2014.12

Language：English Publishing type：Research paper (scientific journal) Publisher：WILEY-BLACKWELL

Compounds based on the pyrroloquinoxaline system can interact with serotonin 5-HT3, cannabinoid CB1, and -opioid receptors. Herein, a chiral pool synthesis of diastereomerically and enantiomerically pure bromolactam (S,R,R,R)-14A is presented. Introduction of the cyclohexenyl ring at the N-atom of (S)-proline derivatives 8 or methyl (S)-pyroglutamate (12) led to the N-cyclohexenyl substituted pyrrolidine derivatives 4 and 13, respectively. All attempts to cyclize the (S)-proline derivatives 4 with a basic pyrrolidine N-atom via [3+2] cycloaddition, aziridination, or bromolactamization failed. Fast aromatization occurred during treatment of cyclohexenamines under halolactamization conditions. In contrast, reaction of a 1:1 mixture of diastereomeric pyroglutamates (S,R)-13bA and (S,S)-13bB with (LiOBu)-Bu-t and NBS provided the tricyclic bromolactam (S,R,R,R)-14A with high diastereoselectivity from (S,R)-13bA, but did not transform the diastereomer (S,S)-13bB. The different behavior of the diastereomeric pyroglutamates (S,R)-13bA and (S,S)-13bB is explained by different energetically favored conformations. Chirality 26:793-800, 2014. (c) 2014 Wiley Periodicals, Inc.

DOI： 10.1002/chir.22350

Web of Science

PubMed

Stereoselective Synthesis of cis,cis-Configured Vicinal Triamines Reviewed

Adrian Sehulte, Susumu Saito, Bernhard Wuensch

EUROPEAN JOURNAL OF ORGANIC CHEMISTRY ( 26 ) page： 5749 - 5756 2014.9

Language：English Publishing type：Research paper (scientific journal) Publisher：WILEY-V C H VERLAG GMBH

The first stereoselective synthesis of a cis, cis-configured vicinal triamine was achieved, starting from N-cyclohexenylpyrrolidone (10). The reaction sequence consists of the stereoselective construction of the trans-configured 1,3-diamide 14, trans-to-cis isomerization via enols or enamines, and subsequent highly stereoselective reduction of the intermediate imine 17D to the amine 18A. The postulated reaction pathway explains the observed stereoconvergence and is supported by calculation of the heats of formation of its intermediates at the PM3 level. LiAlH4 reduction of 18A yielded the tetracyclic aminal 19, which was converted into the pyrrolidinylquinoxaline 7, which showed low to moderate affinity towards. and sigma(1) receptors.

DOI： 10.1002/ejoc.201402685

Web of Science

A Route to propylene from renewable allyl alcohol by photocatalytic transfer hydrogenolysis Reviewed

Joaquim Caner, Zijun Liu, Yuki Takada, Akihiko Kudo, Hiroshi Naka, Susumu Saito

Catal. Sci. Technol. Vol. 4 ( 11 ) page： 4093–4098 2014

Catalytic fluoride triggers dehydrative oxazolidinone synthesis from CO2 Invited Reviewed

Yuki Takada, Siong Wan Foo, Yusuke Yamazaki, Susumu Saito

RSC ADVANCES Vol. 4 ( 92 ) page： 50851 - 50857 2014

Language：English Publishing type：Research paper (scientific journal) Publisher：ROYAL SOC CHEMISTRY

Herein, catalytic fluoride (F-) is demonstrated to be a trigger for dehydrative immobilization of atmospheric pressure CO2, such that reaction of CO2 with beta-amino alcohols derived from natural amino acids gives optically pure oxazolidinones in high yields. A synergistic combination of fluoride and organosilicon agents (e.g., Bu4NF + Ph3SiF or siloxanes) enhances the catalytic activity and functional group compatibility. This system lies at the interface between homogenous and heterogeneous catalysis, and may prove useful for the development of recoverable/reusable siloxane-based CO2 immobilization materials.

DOI： 10.1039/c4ra09609f

Web of Science

Synthesis of propylene from renewable allyl alcohol by photocatalytic transfer hydrogenolysis

Caner Joaquim, Liu Zijun, Takada Yuki, Kudo Akihiko, Naka Hiroshi, Saito Susumu

CATALYSIS SCIENCE & TECHNOLOGY Vol. 4 ( 11 ) page： 4093-4098 2014

The Dual Role of Ruthenium and Alkali Base Catalysts in Enabling a Conceptually New Shortcut to N-Unsubstituted Pyrroles through Unmasked alpha-Amino Aldehydes Reviewed

Kazuki Iida, Takashi Miura, Junki Ando, Susumu Saito

ORGANIC LETTERS Vol. 15 ( 7 ) page： 1436 - 1439 2013.4

Language：English Publishing type：Research paper (scientific journal) Publisher：AMER CHEMICAL SOC

A virtually salt-free and straightforward bimolecular assembly giving N-unsubstituted pyrroles through fully unmasked a-amino aldehydes, which was enabled by the dual effects of a catalytic ruthenium complex and an alkali metal base, is reported. Either solvent-free or acceptorless dehydrogenation facilitates high atom, step, and pot economy, which are otherwise difficult to achieve in multistep operations involving protection/deprotection.

DOI： 10.1021/ol4001262

Web of Science

Reaction of an "Invisible" Frustrated N/B Lewis Pair with Dihydrogen Reviewed

Sina Schwendemann, Shunsuke Oishi, Susumu Saito, Roland Froehlich, Gerald Kehr, Gerhard Erker

CHEMISTRY-AN ASIAN JOURNAL Vol. 8 ( 1 ) page： 212 - 217 2013.1

Language：English Publishing type：Research paper (scientific journal) Publisher：WILEY-V C H VERLAG GMBH

D-(+)-Camphor forms the enamine 2 with piperidine. Compound 2 adds HB(C6F5)(2) at the enamine carbon atom C3 to form a Lewis acid/Lewis base adduct (exo-/endo-isomers of 3). Exposure of 3 to dihydrogen (2.5 bar, room temperature) leads to heterolytic splitting of H-2 to form the H+/H- addition products (4, two diastereoisomers) of the "invisible" frustrated Lewis pairs (5, two diastereoisomers) that were apparently generated in situ by enamine hydroboration under equilibrium conditions.

DOI： 10.1002/asia.201200776

Web of Science

Redox-selective Generation of Aldehydes and H2 from Alcohols under Visible Light Reviewed

Zijun Liu, Joaquim Caner, Akihiko Kudo, Hiroshi Naka, *Susumu Saito

Chem. Eur. J. Vol. 19 page： 9452–9456 2013

Acetals of N,N-dimethylformamides: Ambiphilic behavior in converting carbon dioxide to dialkyl carbonates Reviewed

Yuki Takada, Aki Matsuoka, Ya Du, Hiroshi Naka, Susumu Saito

Chemistry Letters Vol. 42 ( 2 ) page： 146 - 147 2013

Language：English Publishing type：Research paper (scientific journal)

Carbon dioxide is immobilized into dialkyl carbonate using acetals of N,N-dimethylformamide under atmospheric pressure. No special treatment with tailor-made catalysts is needed. Use of dimethyl sulfoxide as a solvent is critical. An ambiphilic mechanism is proposed for the direct synthesis of dialkyl carbonates from acetals and carbon dioxide. © 2013 The Chemical Society of Japan.

DOI： 10.1246/cl.2013.146

Web of Science

Scopus

Catalytic Hydrogenation of Unactivated Amides Using Molecular Catalyst Surface Derived from Ruthenium Complex Invited Reviewed

Takashi Miura, Ingmar E. Held, Shunsuke Oishi, Susumu Saito

Catalysts and Catalysis: Special Issue: Special Issue: Recent Trend in Catalytic Chemicals Synthesis Using Hydrogen Vol. 54 ( 7 ) page： 455–459 2012.12

Catalytic Hydrogenation of Unactivated Amides Using Molecular Catalyst Surface Derived from Ruthenium Complex Invited Reviewed

Takashi Miura, Ingmar E. Held, Shunsuke Oishi, Susumu Saito

Catalysts and Catalysis: Special Issue: Special Issue: Recent Trend in Catalytic Chemicals Synthesis Using Hydrogen Vol. 54 ( 7 ) page： 455–459 2012.12

Double Molecular Recognition with Aminoorganoboron Complexes: Selective Alcoholysis of beta-Dicarbonyl Derivatives Reviewed

Shunsuke Oishi, Susumu Saito

ANGEWANDTE CHEMIE-INTERNATIONAL EDITION Vol. 51 ( 22 ) page： 5395 - 5399 2012

Selective N-Alkylation of Amines with Alcohols by Using Non-Metal-Based Acid-Base Cooperative Catalysis Reviewed

Ya Du, Shunsuke Oishi, Susumu Saito

CHEMISTRY-A EUROPEAN JOURNAL Vol. 17 ( 44 ) page： 12262 - 12267 2011.10

One-Pot Nitrile Aldolization/Hydration Operation Giving beta-Hydroxy Carboxamides Reviewed

Akihiro Goto, Hiroshi Naka, Ryoji Noyori, Susumu Saito

CHEMISTRY-AN ASIAN JOURNAL Vol. 6 ( 7 ) page： 1740 - 1743 2011.7

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Papers - SAITO, Susumu