1890-28-4Relevant academic research and scientific papers
Five-Step Total Synthesis of (±)-Aspidospermidine by a Lactam Strategy via an Azomethine Ylide
Katahara, Seiya,Sugiyama, Yasukazu,Yamane, Mina,Komiya, Yukinori,Sato, Takaaki,Chida, Noritaka
, p. 3058 - 3063 (2021)
A five-step total synthesis of (±)-aspidospermidine (1) based on a lactam strategy is reported. Our synthesis features an iridium-catalyzed reductive Michael addition/[3+2] cycloaddition cascade to give a tricyclic ketone intermediate from a simple lactam via an azomethine ylide. The developed strategy enables easily available lactams to be used as stable surrogates of multisubstituted amines and would be applicable to a unified total synthesis of complex Aspidosperma alkaloids.
Spirocycle assembly through selective tandem ring closing metathesis reactions
Bassindale, Martin J.,Hamley, Peter,Leitner, Andreas,Harrity, Joseph P. A.
, p. 3247 - 3250 (1999)
A range of functionalised spirocyclic systems have been prepared under mild and neutral conditions by tandem selective ring closing olefin metathesis reactions. Additionally, a marked preference for 5-membered ring closure over 7-membered ring closure was observed which appears to be a result of a kinetically favoured cyclisation process.
Preparation method for synthesizing photosensitive compound through Claisen-Schmidt reaction
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Paragraph 0065-0069, (2018/10/19)
The invention provides a preparation method for synthesizing a photosensitive compound through a Claisen-Schmidt reaction. An aldehyde free of alpha-H and a ketone containing alpha-H are selected to be synthesized to obtain the product alpha, beta-unsaturated aldehyde ketone. The preparation method is simple in condition and mild in reaction. The prepared photosensitive compound serving as a hydrogen abstraction type photoinitiator is long in wave length and small in consumption, and has a good initiation effect on monomer PEFDA without adding initiation auxiliaries. Under an ultraviolet lamp,the absorption wavelength is subjected to red shift from 450 to 500 and finally subjected to blue shift to 400 or below. The photosensitive compound has an AIE effect.
Preparation and structural investigations of new hexadentate Schiff base ligands and their bivalent metal complexes, and, catalytic applications of the complexes in allylic and benzylic C-H bond activation
Jyothi,Rao, G. Raghava,Shashank,Sridhar,Reddy, Anjali,Someshwar,Swamy, S. Jagannatha
, p. 535 - 544 (2014/05/06)
The reaction between 2-hydroxybenzaldehyde and piperazine-1,4-diylbis((2- aminophenyl)methanone) or N,N'-(ethane-1,2-diyl)bis(2-amino-N-methyl-benzamide) yields new hexadentate Schiff base ligands, (Z)-piperazine-1,4-diylbis((2-((Z)- (2-hydroxy-benzylidene)amino)phenyl)methanone) (PHMAPM) and 2-((2- hydroxybenzylidene)amino)-N-(2-(2-((E)-(2-hydroxybenzylidene)-amino) -N-methyl-benzimido)ethyl)-N-methylbenzamide (EHBAMB) respectively. PHMAPM crystallizes in the monoclinic space group P21/C. The Co(II), Ni(II) and Cu(II) complexes of these ligands have been prepared and characterized by elemental analyses, conductance, magnetic susceptibility and spectral investigations. The complexes are found to have the formula [M(PHMAPM)] and [M(EHBAMB)] respectively. The catalytic activity of these complexes in allylic and benzylic (C-H) activation has been investigated. The Cu(II) complexes are found to exhibit better activity in acetonitrile as compared to in other solvents.
CXCR4 Receptor Antagonists
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Paragraph 0119; 0120, (2013/11/06)
Disclosed are compounds that are antagonists of the CXCR4 receptor.
Chemoenzymatic and enantiodivergent routes to 1,2-ring-fused bicyclo[2.2.2]octane and related tricyclic frameworks
Austin, Kerrie A. B.,Elsworth, Jon D.,Banwell, Martin G.,Willis, Anthony C.
supporting information; experimental part, p. 751 - 754 (2010/06/17)
New and simple protocols are described for the conversion of the enzymatically-derived and enantiomerically pure cis-1,2-dihydrocatechol 7 (X = I) and its 6-methylated derivative into either antipodal form of compounds embodying the tricyclic frameworks o
Ruthenium-lewis acid catalyzed asymmetric diels-alder reactions between dienes and α,β-unsaturated ketones
Rickerby, Jenny,Vallet, Martial,Bernardinelli, Gerald,Viton, Florian,Kuendig, E. Peter
, p. 3354 - 3368 (2008/03/27)
The complex [Ru(Cp)(R,R-BIPHOP-F)(acetone)][SbF6],(R,R)-1a. was used as catalyst for asymmetric Diels-Alder reactions between dienes (cyclopentadiene, methylcyclopentadienc, isoprene, 2,3-dimethylbutadiene) and α,β-unsaturated ketones (methyl vinyl ketone (MVK). ethyl vinyl ketone, divinyl ketone, α-bromovinyl methyl ketone and α-chlorovinyl methyl ketone). The cycloaddition products were obtained in yields of 50-_90% and with enantioselectivities up to 96% ee. Ethyl vinyl ketone, divinyl ketone and the halogenated vinyl ketones worked best and their reactions with acyclic dienes consistently provided products with >90% ee. α-Chlorovinyl methyl ketone performed better than α-bromovinyl methyl ketone. The reaction also provided a [4.3.1]bicyclic ring system in 95% ee through an intramolecular cycloaddition reaction. Crystal structure determinations of [Ru(Cp)((S,S)-BIPHOP-F)(mvk)]-[SbF6], (S,S)-1b, and [Ru(Cp)((R,R)-Me4BIPHOP-F)(acrolein)][SbF6], (R,R)-2b, provided the basis for a rationalization of the asymmetric induction.
Synthesis of 1,5-bis(triphenylphosphonium)pentan-3-ol dichloride and its application to the preparation of 1,7-di(pyridin-3-yl)heptan-4-ol
Stivanello, Mariano,Leoni, Lucia,Bortolaso, Roberto
, p. 807 - 810 (2013/09/06)
The preparation of 1,7-di(pyridin-3-yl)-heptan-4-ol (1), an important intermediate in the synthesis of a series of novel cancer multidrug resistance (CMR) chemosensitizers, has been accomplished in high overall yield via the new bis-Wittig reagent 1,5-bis(triphenylphosphonium)pentan-3-ol dichloride (6), that can also be used in the preparation of other members of the class of CMRs.
A SIMPLE METHOD FOR THE PRODUCTION OF 1,5-DIHALOGENO-3-PENTANONES AND 1-BROMO-3-PENTANONE - PRECURSORS OF DIVINYL AND ETHYL VINYL KETONES
Sviridov, S. V.,Vasilevskii, D. A.,Kulinkovich, O. G.
, p. 1251 - 1253 (2007/10/02)
The reaction of methyl 3-halogenopropionates with ethylmagnesium bromide in the presence of catalytic amounts of tetraisopropoxytitanium gave the corresponding 1-(2-halogenoethyl)cyclopropanols, the bromination of which with N-bromosuccinimide led to high yields of 1,5-dihalogeno-3-pentanones. 1-Bromo-3-pentanone was obtained by the acid-catalyzed opening of the three-membered ring of 1-(2-bromoethyl)cyclopropanol and also by the bromination of 1-ethylcyclopropanol.The reactions of 1,5-dibromo-3-pentanone with sodium carbonate and sodium sulfide led to good yields of divinyl ketone and 4-tetrahydrothiopyrone respectively.
Reaction of Methanol and Acetone over Metal Ion-Exchanged Forms of Fluoro Tetrasilicic Mica to Form Methyl Vinyl Ketone
Wang, Fey-long,Ueda, Wataru,Morikawa, Yutaka,Ikawa, Tsuneo
, p. 1991 - 1992 (2007/10/02)
Methyl vinyl ketone was obtained at 30-40percent selectivity by the reaction of methanol and acetone at 350 deg.C over Ti(IV)-, Cr(III)-, Mn(II)-, and Sn(IV)-exchanged forms of fluoro tetrasilicic mica (TSM).The addition of oxygen into the feed increased the conversion of acetone and the reaction over Ti(IV)-TSM converted 11percent of acetone fed into methyl vinyl ketone at 85percent selectivity.
