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Nakamura A, Kawasaki S, Toyota K, Yoshifuji M. Reactions of 1,2-di(2-thienyl)-3,4-bis[(2,4,6-tri-t-butylphenyl)phosphinidene]cyclobutene. J Organomet Chem 2007. [DOI: 10.1016/j.jorganchem.2006.08.042] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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53
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Yoshifuji M, Shibayama K, Shima I, Inamoto N. Some reactions of diphosphenes and related species. ACTA ACUST UNITED AC 2006. [DOI: 10.1080/03086648308075955] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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54
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Yoshifuji M, Toyota K, Inamoto N, Hirotsu K, Higuchi T, Nagase S. STRUCTURES OF PHOSPHAETHYLENES AND A 1-PHOSPHAALLENE CONTAINING PHOSPHORUS IN LOWER COORDINATION STATE. ACTA ACUST UNITED AC 2006. [DOI: 10.1080/03086648508072740] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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55
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Freytag M, Ito S, Yoshifuji M. Coordination Behavior of Sterically Protected Phosphaalkenes on the AuCl Moiety Leading to Catalytic 1,6-Enyne Cycloisomerization. Chem Asian J 2006; 1:693-700. [PMID: 17441110 DOI: 10.1002/asia.200600155] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Mes*-substituted 2,3-dimethyl-1,4-diphosphabuta-1,3-diene, 1,2-diphenyl-3,4-diphosphinidenecyclobutene, 2,2-bis(methylsulfanyl)-1-phosphaethene, and 3,3-diphenyl-1,3-diphosphapropenes (Mes* = 2,4,6-tri-tert-butylphenyl) were employed as P ligands of gold(I) complexes. The (E,E)-2,3-dimethyl-1,4-diphosphabuta-1,3-diene functioned as a P2 ligand for digold(I) complex formation with or without intramolecular Au-Au contact, which depends on the conformation of the 1,3-diphosphabuta-1,3-diene. The 1,2-diphenyl-3,4-diphosphinidenecyclobutene, which has a rigid s-cis P=C-C=P skeleton, afforded the corresponding digold(I) complexes with a slight distortion of the planar diphosphinidenecyclobutene framework and intramolecular Au-Au contact. In the case of the 2,2-bis(methylsulfanyl)-1-phosphaethene, only the phosphorus atom coordinated to gold, and the sulfur atom showed almost no intra- or intermolecular coordination to gold. On the other hand, the 1,3-diphosphapropenes behaved as nonequivalent P2 ligands to afford the corresponding mono- and digold(I) complexes. Some phosphaalkene-gold(I) complexes showed catalytic activity for 1,6-enyne cycloisomerization without cocatalysts such as silver hexafluoroantimonate.
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Yoshifuji M, Arduengo, III AJ, Konovalova TA, Kispert LD, Kikuchi M, Ito S. Oxidation of 1,3-Diphosphacyclobutane-2,4-diyl with Ammoniumyl Antimonate and EPR Study of the Corresponding Cation Radical. CHEM LETT 2006. [DOI: 10.1246/cl.2006.1136] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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57
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Murakami H, Matsui Y, Ozawa F, Yoshifuji M. Cyclodehydration of cis–2-butene-1,4-diol with active methylene compounds catalyzed by a diphosphinidenecyclobutene-coordinated palladium complex. J Organomet Chem 2006. [DOI: 10.1016/j.jorganchem.2006.03.011] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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58
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Ito S, Kikuchi M, Yoshifuji M, Arduengo AJ, Konovalova TA, Kispert LD. Preparation and Characterization of an Air-Tolerant 1,3-Diphosphacyclobuten-4-yl Radical. Angew Chem Int Ed Engl 2006; 45:4341-5. [PMID: 16739144 DOI: 10.1002/anie.200600950] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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59
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Ito S, Kikuchi M, Yoshifuji M, Arduengo AJ, Konovalova TA, Kispert LD. Preparation and Characterization of an Air-Tolerant 1,3-Diphosphacyclobuten-4-yl Radical. Angew Chem Int Ed Engl 2006. [DOI: 10.1002/ange.200600950] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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60
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Sasaki S, Mori T, Yoshifuji M. Synthesis and structure of 1-phospholyl- and di(1-phospholyl)acetylenes and the corresponding sulfides. HETEROATOM CHEMISTRY 2006. [DOI: 10.1002/hc.20230] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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61
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Ito S, Nishide K, Yoshifuji M. Structural and Coordination Properties of 3,3-Diphenyl-1- (2,4,6-tri-tert-butylphenyl)-2-(trimethylsilyl)-1,3-diphosphapropene Derivatives Showing Interesting Conformational Features. Organometallics 2006. [DOI: 10.1021/om050972l] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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62
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Yoshifuji M, Ando K, Shibayama K, Inamoto N, Hirotsu K, Higuchi T. Erste Röntgen-Strukturanalyse eines Thiadiphosphirans. Angew Chem Int Ed Engl 2006. [DOI: 10.1002/ange.19830950511] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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63
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Lohmann JJ, Seebach D, Syfrig MA, Yoshifuji M. Lithiiertes N-Pivaloyl-tetrahydroisochinolin - ein Supernucleophil. Angew Chem Int Ed Engl 2006. [DOI: 10.1002/ange.19810930140] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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64
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Ozawa F, Yoshifuji M. Catalytic applications of transition-metal complexes bearing diphosphinidenecyclobutenes (DPCB). Dalton Trans 2006:4987-95. [PMID: 17060985 DOI: 10.1039/b610327h] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The preparation and characterization of sterically protected diphosphinidenecyclobutenes bearing two two-coordinate phosphorus atoms are described from the viewpoint of the development of a novel type of bidentate ligand for transition-metal complexes. They form complexes with group 6 metals such as chromium, molybdenum and tungsten, group 8 metals such as ruthenium, group 10 metals such as palladium and platinum, and group 11 metals such as copper and gold. Some of them can be used as catalysts for synthetic reactions such as cross-coupling of the Sonogashira type, Suzuki-Miyaura coupling, Ullmann coupling, Kosugi-Migita-Stille coupling, cyanation, polymerization of ethylene, dehydrogenative hydrosilylation of ketones, hydroamination of 1,3-butadienes, and direct alkylation or amination of allylic alcohols of Tsuji-Trost reactions.
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Ito S, Freytag M, Yoshifuji M. Structural and coordination properties of 1,2-bis(cyclopropyl)-3,4-bis(2,4,6-tri-tert-butylphenyl)-3,4-diphosphinidenecyclobutene prepared by dehydrogenative homocoupling of 3-cyclopropyl-1-(2,4,6-tri-tert-butylphenyl)-1-phosphaallene. Dalton Trans 2006:710-3. [PMID: 16429175 DOI: 10.1039/b510432g] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
According to a protocol for the synthesis of phosphaallenes we recently established, 3-cyclopropyl-1-(2,4,6-tri-tert-butylphenyl)-1-phosphallene was obtained from (Z)-2-bromo-3-cyclopropyl-1-(2,4,6-tri-tert-butylphenyl)-1-phosphapropene. A novel bidentate ligand, 1,2-bis(cyclopropyl)-3,4-bis(2,4,6-tri-tert-butylphenyl)-3,4-diphosphinidenecyclobutene, was prepared by oxidative homocoupling of 3-cyclopropyl-1-(2,4,6-tri-tert-butylphenyl)-1-phosphaallene in the presence of butyllithium, together with the generation of hydrogen gas. The 1,2-bis(cyclopropyl)-3,4-diphosphinidenecyclobutene was allowed to react with (tht)AuCl (tht = tetrahydrothiophene) to afford the corresponding digold(I) complex of a six-membered metallacycle containing the P=C-C=P skeleton. The molecular structures of the 2-bromo-3-cyclopropyl-1-phosphapropene, 1,2-bis(cyclopropyl)-3,4-diphosphinidenecyclobutene and the digold complex were unambiguously determined by X-ray crystallography and are discussed from the point of view of the cyclopropyl conjugation.
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Sutoh K, Sasaki S, Yoshifuji M. Synthesis and Redox Properties of Crowded Triarylphosphines Possessing Ferrocenyl Groups. Inorg Chem 2005; 45:992-8. [PMID: 16441105 DOI: 10.1021/ic051038l] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Crowded triarylphosphines possessing ferrocenyl groups [(4-ferrocenyl-2,6-diisopropylphenyl)(n)(2,4,6-triisopropylphenyl)(3-n)P (5a, n = 1; 5b, n = 2; 5c, n = 3)] were synthesized by the reaction of the corresponding arylcopper(I) reagents with the diarylchlorophosphines. Structures of the triarylphosphines were studied by 1H, 13C, and 31P NMR spectroscopies, and the characteristic patterns of the proton signals of the 2,6-isopropyl groups and upfielded 31P chemical shifts suggest structural similarities of the triarylphosphine moiety to the previously reported tris(2,4,6-triisopropylphenyl)phosphine (2). X-ray crystallography of 5c also revealed that the structure around the phosphorus is similar to that of 1, where the average bond angle and length around the phosphorus atom are 110.8 degrees and 1.854 A, respectively. According to the electrochemical measurements, phosphines 5a, 5b, and 5c are reversibly oxidized in two, three, and four steps, respectively, which suggests significant electronic interaction among the triarylphosphine and the ferrocene redox centers as well as weak interaction among the ferrocene redox centers. The EPR spectra obtained at cryogenic temperature after oxidation of phosphines 5a, 5b, and 5c are superpositions of those for the cation radicals of the crowded triarylphosphine and ferricinium. The solution spectra obtained at 293 K, which consist of two lines typical of the cation radical of the crowded triarylphosphines, become weaker as the number of the ferrocenyl groups increases and the cation radical of 5c does not show EPR signals. These findings suggest not only instability of the tetra(cation radical) of 5c but also the course of oxidation where the ferrocenyl groups in the periphery of the molecules are oxidized at first.
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Jensen RS, Gajare AS, Toyota K, Yoshifuji M, Ozawa F. A convenient procedure for palladium catalyzed cyanation using a unique bidentate phosphorus ligand. Tetrahedron Lett 2005. [DOI: 10.1016/j.tetlet.2005.10.052] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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68
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Sasaki S, Murakami F, Yoshifuji M. Synthesis and Redox Properties of (3-Phenothiazinomesityl)- and (4-Phenothiazinoduryl)dimesitylphosphines and the Corresponding Arsines. Organometallics 2005. [DOI: 10.1021/om050522t] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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69
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Nishide K, Liang H, Ito S, Yoshifuji M. Preparation and properties of palladium(II) complexes of 3-oxo-1-(2,4,6-tri-t-butylphenyl)-1,3-diphosphapropenes. J Organomet Chem 2005. [DOI: 10.1016/j.jorganchem.2005.07.075] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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70
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Ito S, Miyake H, Yoshifuji M, Höltzl T, Veszprémi T. Synthesis of phosphorus ylides bearing a P-H bond from a kinetically stabilized 1,3,6-triphosphafulvene. Chemistry 2005; 11:5960-5. [PMID: 16052657 DOI: 10.1002/chem.200500374] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
In mixing 2,4,6-tris(2,4,6-tri-tert-butylphenyl)-1,3,6-triphosphafulvene with alkyllithium compounds and acetic acid, both of nucleophilic alkylation and electrophilic protonation occurred at the exo sp2-phosphorus atoms to afford [2,4-bis(2,4,6-tri-tert-butylphenyl)-1,3-diphosphacyclopentadienylidene](alkyl)(2,4,6-tri-tert-butylphenyl)phosphoranes which are phosphorus ylides that bear a P-H bond. A phosphorus ylide bearing both P-H and P-F bonds was obtained by reaction of 2,4,6-tris(2,4,6-tri-tert-butylphenyl)-1,3,6-triphosphafulvene with hydrogen tetrafluoroborate, and the structure was determined by X-ray crystallography. Both P=C double bond and P(+)-C(-) zwitterionic character was indicated by the metric parameters. The isolated phosphorus ylide bearing a P-H bond, [2,4-bis(2,4,6-tri-tert-butylphenyl)-1,3-diphosphacyclopentadienylidene](2,4,6-tri-tert-butylphenyl)phosphorane, showed no isomerization by H-migration to the corresponding phosphinodiphospholes, probably due to the pi-accepting ability of the unsaturated PC bonds and aromaticity of the C3P2 ring. The ylide structure and aromaticity of 2,4-diphosphacyclopenta-2,4-dienylidenephosphorane was characterized by theoretical calculations. In addition, the regioselective protonation of the lithiated phosphinodiphospholes generated from the 1,3,6-triphosphafulvene is discussed.
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Murakami F, Sasaki S, Yoshifuji M. Phosphaquinomethane and Phosphathienoquinomethanes, and Their Anion Radicals. J Am Chem Soc 2005; 127:8926-7. [PMID: 15969550 DOI: 10.1021/ja052271l] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Phosphaquinomethane and phosphathienoquinomethanes sterically protected by Mes* (Mes* = 2,4,6-tri-tert-butylphenyl) were synthesized by 1,6-dehydration of the corresponding 4-phosphinoaryl carbinols. Structural similarities to the conventional quinoid compounds were revealed by 1H, 13C, and 31P NMR study and further confirmed by X-ray crystallography of the phosphathienoquinomethane. The corresponding anion radicals were generated by reduction with sodium, and considerable delocalization of an unpaired electron was demonstrated by EPR.
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Kawasaki S, Nakamura A, Toyota K, Yoshifuji M. The Electronic Effects of Bulky Aryl Substituents on Low Coordinated Phosphorus Atoms in Diphosphenes and Phosphaalkenes by Functionalization at the Para Position. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2005. [DOI: 10.1246/bcsj.78.1110] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Ito S, Sekiguchi S, Freytag M, Yoshifuji M. An Efficient Synthetic Method of 1-(2,4,6-Tri-t-butylphenyl)-3-phenyl-1-phosphaallenes [Mes*P=C=CR–Ph; R = H, SiMe3] from Dibromophosphaethene [Mes*P=CBr2] (Mes*= 2,4,6-t-Bu3C6H2). BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2005. [DOI: 10.1246/bcsj.78.1142] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Kawasaki S, Fujita T, Toyota K, Yoshifuji M. Preparation and Properties of Fluorenylidene(phenyl)phosphines Bearing Bulky Groups with Electron-Donating Substituents in the Ortho Position on the Phenyl Group. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2005. [DOI: 10.1246/bcsj.78.1082] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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75
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Kawasaki S, Nakamura A, Toyota K, Yoshifuji M. Preparation and Properties of 1,2-Diferrocenyl-Substituted 3,4-Diphosphinidenecyclobutenes and Their Complexes: The First Application of a Diphosphinidenecyclobutene Unit as a Linker of Functional Moieties. Organometallics 2005. [DOI: 10.1021/om0500772] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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