6583-62-6Relevant academic research and scientific papers
Control of Homocoupling Versus Reduction in Titanium(III)-Mediated Radical Opening of Styrene Oxides
González-Delgado, José A.,Arteaga, Jesús F.
, p. 7864 - 7869 (2019/12/27)
We describe the use of titanocene monochloride in the implementation of an experimental procedure that enables control of the homolytic opening of styrene oxides in a chemoselectively controlled manner. This leads either to homocoupling products or to phenethyl alcohol derivatives. The process occurs via the generation of benzyl radicals, which may undergo a) recombination or b) reduction, yielding benzyl-Ti(IV) species upon subsequent addition of H2O to the corresponding hydroxylated compounds. The main goal of this work is the study of the reactivity pattern of styrene oxides towards the formation of the mentioned products, thereby adding value to this interesting building block.
Radical titanocene promoted coupling of epoxides and vinyl sulfones
Fernndez-Mateos, Alfonso,Encinas-Madrazo, Soledad,Herrero-Teijn, Pablo,Gonzlez, Rosa Rubio
, p. 548 - 555 (2015/01/30)
A radical coupling reaction of diverse vinyl sulfones and epoxides was mediated by Cp2TiCl (Cp = cyclopentadienyl) to provide a straightforward synthetic pathway to hydroxy sulfones. The reaction was successfully achieved by using either an excess or a catalytic amount of the TiIII reagent. The scope of the reaction was studied for several different functionalized and substituted epoxides and vinyl sulfones.
A facile synthesis of 5,6-dihydro-4H-pyrrolo[3,4-d]thiazole and other pyrrolidine-fused aromatic ring systems via one-step cyclization from diols
Yoshikawa, Kenji,Nagata, Tsutomu,Yoshino, Toshiharu,Nakamoto, Yumi,Haginoya, Noriyasu,Muto, Ryo,Mochizuki, Akiyoshi,Kanno, Hideyuki,Ohta, Toshiharu
experimental part, p. 1711 - 1720 (2012/09/07)
A facile synthetic method of 5,6-dihydro-4H-pyrrolo[3,4-d]thiazole, which is a subunit of a potent factor Xa (fXa) inhibitor was developed. This new approach employs one-step cyclization from a diol and can be applied to the syntheses of other pyrrolidine-fused aromatic ring sytems.
Diastereocontrol in asymmetric allyl-allyl cross-coupling: Stereocontrolled reaction of prochiral allylboronates with prochiral allyl chlorides
Brozek, Laura A.,Ardolino, Michael J.,Morken, James P.
, p. 16778 - 16781 (2011/12/04)
Palladium-catalyzed allyl-allyl cross-coupling was investigated with substituted prochiral allylic boronates. These reactions deliver products bearing adjacent stereocenters, and the issue of diastereocontrol is therefore paramount. Under appropriately mo
Titanocene-promoted intermolecular couplings of epoxides with nitriles. An easy access to β-hydroxyketones
Fernandez-Mateos,Encinas Madrazo,Herrero Teijon,Rubio Gonzalez
supporting information; experimental part, p. 3913 - 3918 (2009/10/20)
(Chemical Equation Presented) Radical couplings of epoxides and nitriles mediated by Cp2TiCl provide a diastereoselective route to the synthesis of β-hydroxyketones. The conditions of this "aldol- like" reaction are mild enough to avoid the dehydration of the β-hydroxyketone. The scope of the coupling reaction with functionalized and tetrasubstituted epoxides has been studied. The radical character of the coupling reactions is demonstrated.
Convenient methods for synthesis of C2-symmetric diphenyltetrahydrothiophenes
Periasamy, Mariappan,Ramani, Gurubrahamam,Muthukumaragopal, Gopal P.
experimental part, p. 1739 - 1743 (2009/12/27)
Racemic and optically pure (-)-(3R,4R)-3,4-diphenyltetrahydrothiophene, (+)-(2S,5S)-2,5-diphenyltetrahydrothiophene, and (-)-(3S,6S)-3,6-diphenyl-1,2- dithiane were synthesized by use, in the crucial steps, of the easy-to-handle borane systems tetrabutylammonium borohydride-iodine and tetrabutylammonium borohydride-iodomethane. Georg Thieme Verlag Stuttgart.
Ruthenium(salen)-catalyzed aerobic oxidative desymmetrizatin of meso-diols and its kinetics
Shimizu, Hideki,Onitsuka, Satoaki,Egami, Hiromichi,Katsuki, Tsutomu
, p. 5396 - 5413 (2007/10/03)
Chiral (nitrosyl)ruthenium(salen) complexes were found to be efficient catalysts for aerobic oxidative desymmetrization of meso-diols under photoirradiation to give optically active tactols. The scope of the applicability of this reaction ranges widely from acyclic diols to mono-cyclic diols, although fine ligand-tuning of the ruthenium(salen) complexes was required to attain high enantioselectivity (up to 93% ee). In particular, the nature of the apical ligand was found to affect not only enantioselectivity but also kinetics of the desymmetrization reaction. Spectroscopic analysis of the oxidation disclosed that irradiation of visible light is indispensable not only for dissociation of the nitrosyl ligand but also for single electron transfer from the alcohol-bound ruthenium ion to dioxygen.
Novel reductive cleavage reaction of α-halo epoxides with SMI2: Synthesis of cyclopropanols
Park, Heui Sul,Chung, So Hee,Kim, Yong Hae
, p. 1073 - 1074 (2007/10/03)
Aryl substituted α-halo epoxide reacted with SmI2 to give the cyclopropanols in the presence of HMPA, while allyl alcohols were yielded in the absence of HMPA.
REACTIONS OF OXIRANES WITH ALKALI METALS: INTERMEDIACY OF RADICAL-ANIONS
Gurudutt, K. N.,Pasha, M. A.,Ravindranath, B.,Srinivas, P.
, p. 1629 - 1632 (2007/10/02)
Reaction of oxiranes with alkali metals in aprotic solvents yields a variety of products depending on the nature of the metal and the structure of the oxirane.Deoxygenation to olefins is the major reaction in case of lithium.Rearrangement to carbonyl compounds, reduction to alcohols and formation of dimeric products occur when oxiranes are treated with sodium.All the reactions could be rationalised by a mechanism involving an initial single electron transfer leading to the formation of radical-anion intermediate.
A New Preparative Method for (E)-2,3-Diarylbut-2-enedials
Toda, Fumio,Takehira, Yoshikazu,Kataoka, Yutaka,Mori, Koji,Sato, Tamie,Segawa, Mari
, p. 1234 - 1235 (2007/10/02)
Reaction of 1,2-diaryl-3,4-dibromocyclo-but-1-enes (4) with silver perchlorate in the presence of water gave (E)-2,3-diarylbut-2-enedials (5), which when treated with acid were converted into 2,3-diarylbut-2-en-4-olides (6).
