神奈川大学 工学部 物質生命化学科 岡本専太郎研究室 有機反応デザイン研究室
Title.jpg

I
HOME > Research

research.jpgBLANC.tiffChemistries in Okamoto Laboratory.jpg

ページの先頭へ

Recent Works

Ti chemistry

Sentaro Okamoto, Takeshi Yamada, Yu-ki Tanabe, Masaki Sakaia
"Alkyne [2+2+2] Cyclotrimerization Catalyzed by a Low-Valent Titanium Reagent Derived from CpTiX3 (X = Cl, O-i-Pr), Me3SiCl, and Mg or Zn”,
Organomettalics, 2018, 37, 4431-4438.
[Link]
CpTiCl3.tif

Suchithra Madhavan, Hiromasa Takagi, Shunpei Fukuda and Sentaro Okamoto, "Low−valent titanium−catalyzed deprotection of allyl- and propargyl-carbamates to amines”,
Tetrahedron Letters, 2016, 57, 2074-2077.
[Link]
TOC.tif


Sentaro Okamoto, “Synthetic Reactions Using Low-Valent Titanium Reagents Derived from Ti(OP)4 or CpTiX3 (X = O-i-Pr or Cl) in the Presence of Me3SiCl and Mg”,
The Chemical Record, 2016, 16, 857-872

[Link]
TOC graphic.tif


Sentaro Okamoto, "Synthetic Reactions Using A Low-Valent Titanium Reagent Ti(OR)4/Me3SiCl/Mg,”
Yuki Gosei Kagaku Kyokaishi, 2014, 72, 382-392.
Table of Contents.tif


Generation of A Low-Valent Titanium from Titanatrane and Its Catalytic Reactions: Radical Ring Opening of Oxetanes
[Adv. Synth. Catal. 2013, 355, 2151-2157]
LVT Oxetane.jpg


Non-Cp Titanium Alkoxide-Based Homolytic Ring-Opening of Epoxides by An Intramolecular Hydrogen Abstraction in beta-Titanoxy Radical Intermediates
[Chemical Communications, 2011, 47, 7857-7859.]
droppedImage_4-1.jpg


Ti(O-i-Pr)4/Me3SiCl/Mg-Mediated Reductive Cleavage of Sulfonamides and Sulfonates To Amines and Alcohols
[Organic Letters, 2011, 13, 2626-2629.]
Highlighted in Organic Chemistry Highlights. Highlighted in Organic Chemistry Portal Picked up in ChemInform
droppedImage_5-1.jpg


McMurry coupling of aryl aldehydes and imino pinacol coupling mediated by Ti(O-i-Pr)4/Me3SiCl/Mg reagent
[Tetrahedron Letters, 2010, 51, 387-390]
Picked up by SYNFACTS(2010, p 346
droppedImage_6-1.jpg


Two-step allylic carbon insertion between ketone carbonyl and carbons giving a-quaternary a-vinyl ketones
[Tetrahedron Letters, 2008, 49, 6724-6727]
Picked up in ChemInform
droppedImage_7-1.jpg


Selective Cleavage of Allyl and Propargyl Ethers to Alcohols Catalyzed by Ti(O-i-Pr)4/MXn/M
[Organic Letters, 2007, 9, 773-776]
Picked up in ChemInform
droppedImage_8-1.jpg


Ti(II)-Mediated domino cyclization of 2-functionalized 1-halo-2,n-enynes (n = 7, 8) to bicyclic compounds
[Tetrahedron Letters, 2006, 47, 7537-7540]
Picked up in ChemInform
droppedImage_9-1.jpg


Synthesis of N-substituted 2-arylpyrroles by the reaction of (eta2-imine)titanium complexes with 3,3-diethoxypropyne
[Tetrahedron Letters, 2006, 47, 6209-6212]
Highlighted in SYNFACTS(2006, p.1223)
droppedImage_10-1.jpg


Formation of azatitanacyclopentanes from ene-imines and a Ti(O-i-Pr)4/2i-PrMgX reagent and their synthetic reactions
[Tetrahedron Lettrs, 2004, 45, 9037-9040]
Picked up in ChmeInform
droppedImage_11-1.jpg

Fe, Co, Ni catalysis

Yu-ki Sugiyama, Shiori Heigozono, Kazuhiro Tamura, Sentaro Okamoto, "Iron-Catalyzed Reductive Metalation–Allylation and Metalative Cyclization of 2,3-Disubstituted Oxetanes and Their Stereoselectivity”,
Synthesis, 2016, 48, 2823-2828.[Link]
Graphical Abstract.tif


Catalytic [2 + 2 + 2] Cycloaddition Polymerization of Diyne–Nitrile Monomers in the Presence of CoCl2-6H2O/Diphosphine/Zn

J. Polym. Sci. A: Polym. Chem. 2016, 54, 345-351..
Graph Abs HP.tiff

Iron-Catalyzed Reductive Magnesiation of Oxetanes to Gen-erate (3-Oxidopropyl)magnesium Reagents
Org. Lett. 2014, 16,6278-6281.
TOC graph.tif

Cobalt-Catalyzed Cross Addition of Silylacetylenes to Internal Alkynes,
[J. Org. Chem. 2013, 78, 3583-3591]
droppedImage_12-1.jpg


From Development of Catalysts for Alkyne and Alkyne/Nitrile [2 + 2 + 2] Cycloaddition Reactions to Their Use in Polymerization Reactions,
[Synlett, 2013, 1044-1060] (Account)
droppedImage_13-1.jpg


Remarkable Activation of An Alkyne [2 + 2 + 2] Cycloaddition Catalyst, 2-Iminomethylpyridine (Dipimp)/CoCl2-6H2O/Zn, by a Phthalate Additive
[SYNLETT 2012, 23, 2549-2553]
droppedImage_14-1.jpg


Synthesis of 2,2’-Bipyridines by Transition Metal-Catalyzed Alkyne/Nitrile [2 + 2 + 2] Cycloaddition Reactions
[Review in: Heterocycles, Heterocycles, 2012, 85, 1579-1602.]
droppedImage_15-1.jpg


Chain-Growth Cycloaddition Polymerization via a Catalytic Alkyne [2 + 2 + 2] Cyclotrimerization Reaction and Its Application to One-shot Spontaneous Block Copolymerization
[J. Am. Chem. Soc. 2011, 133, 9712-9715.]
Highlighted in ACS Noteworthy Chemistry and Selected as SYNFACT of the month
droppedImage_1-3.jpg


Regioselective Synthesis of Substituted Pyridines and 2,2'-Dipyridines by a Cobalt-Catalyzed [2 + 2 + 2] Cycloaddition of a,w-diynes with Nitriles
[Synthesis 2011, 2247-2254.] (special issue) See also the Correction: Errata (2011, 3928)
Picked up in ChemInform
droppedImage_16-1.jpg


Quick Access to Diverse Polymerizable Molecules (a Monomer Library) by Catalytic [2 + 2 + 2] Cycloaddition Reactions of Functionalized Alkynes
[ Macromolecules, 2010, 43, 2213-2218 ]
droppedImage_3-1.jpg

Synthesis of substituted anthracenes, pentaphenes and trinaphthylenes via alkyne cyclotrimerization reaction
[Tetrahedron Letters, 2010, 51, 1313-1316.]
Picked up in SYNFACTS(2010, p 423)
droppedImage_17-1.jpg


Selective Dimerization of 1,6-Diynes Catalyzed by Ionic Liquid-Supported Nickel Complexes in An Ionic Liquid/Toluene Biphasic System,
[Chem. Commun. 2009, 439-441.]
Picked up by SYNFACTS(2009, p 458 and ChemInform
droppedImage_18-1.jpg


Synthesis of Substituted 2,2'-Bipyridines and 2,2':6,2"-Terpyridines by Cobalt-Catalyzed Cycloaddition Reactions of Nitriles and a,w-Diynes with Exclusive Regioselectivity,
[Advanced Synthesis & Catalysis, 2008, 350, 143-152.]
Picked up in ChemInform
droppedImage_19-1.jpg


Efficient Activation of 2-Iminomethylpyridine/Cobalt-Baesd Alkyne [2 + 2 + 2] Cycloaddition Catalyst by Addition of a Silver Salt
[Advanced Synthesis & Catalysis, 2007, 349, 2368-2374]
droppedImage_20-1.jpg


On-Demand Generation of an Efficient Catalyst for Pyridine Formation from Unactivated Nitriles and -Diynes Using CoCl2-6H2O, dppe and Zn
[Organic Letters, 2007, 9, 931-934]
droppedImage_21-1.jpg


Iron-catalyzed intramolecular cyclotrimerization of triynes to annulated benzenes
[J. Organometallic Chemistry, 2006, 691, 3129-3136]
Picked up in ChemInform
droppedImage_22-1.jpg


A Highly Practical Instant Catalyst for Cyclotrimerization of Alkynes to Substituted Benzenes
[Organic Letters, 2006, 8, 1439-1442]
Picked up in ChemInform
droppedImage_23-1.jpg


Cobalt-catalyzed benzyl-alkynyl coupling
[Tetrahedron Letters, 2006, 47, 2591-2594]
Picked up in ChemInform
droppedImage_24-1.jpg


Intramolecular Cyclotrimerization of Triynes Catalyzedby N-Heterocyclic Carbene-CoCl2/Zn or -FeCl3/Zn
[Organic Letters, 2005, 7, 3065-3067]
Picked up in ChemInform
droppedImage_25-1.jpg


Cobalt-catalyzed mono-coupling of R3SiCH2MgCl with 1,2-dihalogenoethylene: A general route to gamma-substituted (E)-allylsilanes
[Tetrahedron Letters, 2004, 45, 4677-4679]
Picked up in ChmeInform
droppedImage_26-1.jpg

Cu catalysis

Copper-catalyzed intramolecular hydroamination of allenylamines to 3-pyrrolines or 2-alkenylpyrrolidnes
[Tetrahedonr Letters 2008, 49, 6529-6532]
Picked up in ChmeInform
droppedImage_27-1.jpg


Allylic Substitution Reactions with Grignard Reagents Catalyzed by Imidazolium and 4,5-Dihydroimidazolium Carbene-CuCl Complexes
[J. Organometallic Chemistry, 2005, 690, 6001-6007 and see also Erratum]
Picked up in ChmeInform
droppedImage_28-1.jpg


gamma-Selective allylic substitution reaction with Grignard reagents catalyzed by copper N-heterocyclic carbene complexes and its application to enantioselective synthesis
[Tetrahedron Letters, 2004, 45, 5585-5588]
Picked up in ChmeInform
droppedImage_29-1.jpg

Other Metals

Silica-supported silver as a green and sustainable catalyst for [3+2] cycloaddition reaction of azomethine ylides with 2’-hydroxychalcone derivatives
[ChemCatChem, 2018, 10, 2014-2018.]
TOC.tif


Grignard allylic substitution reaction catalyzed by 1,2,3-triazol-5-ylidene magnesium complexes
[Tetrahedron Letters, 2013, 54, 1360-1363]
droppedImage_30.jpg


Grignard allylic substitution catalyzed by imidazol-2-ylidene- and imidazol-4-ylidene-magnesium complexes
[Tetrahedron Letters, 2010, 51, 5704-5707]
droppedImage_31.jpg


Carbonyl reduction with CaH2 and R3SiCl catalyzed by ZnCl2"
[Tetrahedron Letters, 2007, 47, 9120-9123.]
Picked up in ChemInform
droppedImage_32.jpg


Use of CaH2 as a reductive hydride source: Reduction of ketones and imines with CaH2/ZnX2 in the presence of a Lewis acid
[Tetrahedron Letters, 2005, 46, 1667-1669]
Picked up in Best Synthetic Methods: Reduction in Organic Chemistry Highlights. Picked up in ChemInform
droppedImage_33.jpg

Non-metal Catalysis

Simple and practical method for selective acylation of primary hydroxy group catalyzed by N-methyl-2-phenylimidazole (Ph-NMI) or 2-phenylimidazo[2,1-b]benzothiazoles (Ph-IBT)
[Tetrahedron Leetrs 2014, 55, 7039-7042.]
Graph Abs.jpg

Structure–activity relationship of dihydroimidazo-, dihydropyrimido, tetrahydrodiazepino-[2,1-b]-thiazoles and -benzothiazoles as an acylation catalyst
[Tetrahedron Lett. 2014, 55, 1909-1912]
DHPB.jpg


Synthesis and Catalytic Properties of 4-Aryl-2,3-dihydro-4H-pyrimido[2,3-b]benzothiazoles for Asymmetric Acyl or Carboxyl Group Transfer Reactions
[J. Org. Chem. 2011, 76, 6678-6685]
Picked up in ChemInform and Highlighted in Organic Chemistry Portal
droppedImage_34.jpg


Activity and behavior of imidazolium salts as a phase transfer catalyst for a liquid-liquid phase system
[Tetrahedron Letters, 2006, 47, 8055-8058]
droppedImage_35.jpg


Unexpected reactivity of annulated 3H-benzothiazol-2-ylideneamines as an acyl transfer catalyst
[Tetrahedron Letters, 2006, 47, 4347-4350]
droppedImage_36.jpg

Macromolecules

Synthesis and properties of folded π-stacking polymers having J-aggregative, alternative, and staggered assembling structures
Polymer, 2016, 97, 550-558.
[Link]

TOC.tif


Catalytic [2 + 2 + 2] Cycloaddition Polymerization of Diyne–Nitrile Monomers in the Presence of CoCl2-6H2O/Diphosphine/Zn

J. Polym. Sci. A: Polym. Chem. 2016, 54, 345-351.
Graph Abs HP.tiff

Design and synthesis of 2-(1,3-dialkoxy-2-methylpropan-2-yl)-1,3-diarylpropanes as tethering units for folded H-stacking polymers
Tetrahedron Letters, 2014, 55, 2649-2653.
TOC01.tif

Synthesis and Properties of Through-Space Conjugated Polymers Based on pi–pi Stacked 1,3-Biarylpropane Tethering Units
[J. Polymer Science Part A: Polymer Chemistry, 2013, 51, 3412-3419]
droppedImage-4.jpg


Synthesis of [—CH2C(CO2Et)2CH2Ar—]n Polymers and Their Unique Optical Properties by Through-Space Interactions between Ar and C=O Groups
[J.Polymer Science Part A: Polymer Chemistry, 2012, 50, 1707-1716]
Graphical Abstract .jpg


Chain-Growth Cycloaddition Polymerization via a Catalytic Alkyne [2 + 2 + 2] Cyclotrimerization Reaction and Its Application to One-shot Spontaneous Block Copolymerization
[J. Am. Chem. Soc. 2011, 133, 9712-9715.]
Highlighted in ACS Noteworthy Chemistry and Selected as SYNFACT of the month
droppedImage_1-3.jpg


Folded H-Stacking Polymers by Conformational Control with 2-Substituted Trimethylene Tethers
[Macromolecules, 2010, 43, 6562-6569.]
droppedImage_2-1.jpg


Quick Access to Diverse Polymerizable Molecules (a Monomer Library) by Catalytic [2 + 2 + 2] Cycloaddition Reactions of Functionalized Alkynes
[ Macromolecules, 2010, 43, 2213-2218 ]
droppedImage_3-1.jpg



Related to Synthesis of Biologically Active Compounds

Preparation of 2-hydroxy A-ring precursors for synthesis of vitamin D3 analogues from lyxose
[Tetrahedron Lett. 2015, 56 ,2315-2318.]
TOC.jpg

Generation of A Low-Valent Titanium from Titanatrane and Its Catalytic Reactions: Radical Ring Opening of Oxetanes
[Adv. Synth. Catal. 2013, 355, 2151-2157]
LVT Oxetane_1.jpg


Stereoselective construction of 3a-methylhydrindanes starting from 2,7-enynol derivatives based on Ti(II)-mediated cyclization and Ru-catalyzed ring-closing metathesis
[Tetrahedron Letters, 2006, 47, 5181-5185]
Picked up in ChemInform
droppedImage_37.jpg


Formation of azatitanacyclopentanes from ene-imines and a Ti(O-i-Pr)4/2i-PrMgX reagent and their synthetic reactions
[Tetrahedron Lettrs, 2004, 45, 9037-9040]
Picked up in ChmeInform
droppedImage_38.jpg

Previously Synthesized Compounds
synthesized_1.jpg

関連リンクなどLinkIcon