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Search for "chelate complexes" in Full Text gives 9 result(s) in Beilstein Journal of Organic Chemistry.
Ruthenium-based olefin metathesis catalysts with monodentate unsymmetrical NHC ligands
- Veronica Paradiso,
- Chiara Costabile and
- Fabia Grisi
Beilstein J. Org. Chem. 2018, 14, 3122–3149, doi:10.3762/bjoc.14.292
- cyclization, although the catalytic activity of the homologous series 98–100 was found to be strongly dependent on the tether length between the alkene group and the metal center. This effect is likely related to their different ability in forming the corresponding chelate complexes in situ (Figure 19
Graphical Abstract
Figure 1: Second-generation Grubbs (GII), Hoveyda (HGII), Grela (Gre-II), Blechert (Ble-II) and indenylidene-...
Figure 2: Grubbs (1a) and Hoveyda-type (1b) complexes with N-phenyl, N’-mesityl NHCs.
Figure 3: C–H insertion product 2.
Figure 4: Grubbs (3a–6a) and Hoveyda-type (3b–6b) complexes with N-fluorophenyl, N’-aryl NHCs.
Scheme 1: RCM of diethyl diallylmalonate (7).
Scheme 2: RCM of diethyl allylmethallylmalonate (9).
Scheme 3: RCM of diethyl dimethallylmalonate (11).
Scheme 4: CM of allylbenzene (13) with cis-1,4-diacetoxy-2-butene (14).
Scheme 5: ROMP of 1,5-cyclooctadiene (16).
Figure 5: Grubbs (18a–21a) and Hoveyda-type (18b–21b) catalysts bearing uNHCs with a hexafluoroisopropylalkox...
Figure 6: A Grubbs-type complex with an N-adamantyl, N’-mesityl NHC 22 and the Hoveyda-type complex with a ch...
Figure 7: Grubbs (24a and 25a) and Hoveyda-type (24b and 25b) complexes with N-alkyl, N’-mesityl NHCs.
Figure 8: Grubbs-type complexes 31–34 with N-alkyl, N’-mesityl NHCs.
Figure 9: Grubbs-type complex 35 with an N-cyclohexyl, N’-2,6-diisopropylphenyl NHC.
Figure 10: Hoveyda-type complexes with an N-alkyl, N’-mesityl (36, 37) and an N-alkyl, N’-2,6-diisopropylpheny...
Figure 11: Indenylidene-type complexes 41–43 with N-alkyl, N’-mesityl NHCs.
Figure 12: Grubbs-type complex 44 and its monopyridine derivative 45 containing a chiral uNHC.
Scheme 6: Alternating copolymerization of 46 with 47 and 48.
Figure 13: Pyridine-containing complexes 49–52 and Grubbs-type complex 53.
Figure 14: Hoveyda-type complexes 54–58 in the alternating ROMP of NBE (46) and COE (47).
Figure 15: Catalysts 59 and 60 in the tandem RO–RCM of 47.
Figure 16: Hoveyda-type complexes 61–69 with N-alkyl, N’-aryl NHCs.
Scheme 7: Ethenolysis of methyl oleate (70).
Scheme 8: AROCM of cis-5-norbornene-endo-2,3-dicarboxylic anhydride (75) with styrene.
Figure 17: Hoveyda-type catalysts 79–82 with N-tert-butyl, N’-aryl NHCs.
Scheme 9: Latent ROMP of 83 with catalyst 82.
Figure 18: Indenylidene and Hoveyda-type complexes 85–92 with N-cycloalkyl, N’-mesityl NHCs.
Scheme 10: RCM of N,N-dimethallyl-N-tosylamide (93) with catalyst 85.
Scheme 11: Self metathesis of 13 with catalyst 85.
Figure 19: Grubbs-type complexes 98–104 with N-alkyl, N’-mesityl NHCs.
Figure 20: Grubbs-type complexes 105–115 with N-alkyl, N’-mesityl ligands.
Figure 21: Complexes 116 and 117 bearing a carbohydrate-based NHC.
Figure 22: Complexes 118 and 119 bearing a hemilabile amino-tethered NHC.
Figure 23: Indenylidene-type complexes 120–126 with N-benzyl, N’-mesityl NHCs.
Scheme 12: Diastereoselective ring-rearrangement metathesis (dRRM) of cyclopentene 131.
Figure 24: Indenylidene-type complexes 134 and 135 with N-nitrobenzyl, N’-mesityl NHCs.
Figure 25: Hoveyda-type complexes 136–138 with N-benzyl, N’-mesityl NHCs.
Figure 26: Hoveyda-type complexes 139–142 with N-benzyl, N’-Dipp NHC.
Figure 27: Indenylidene (143–146) and Hoveyda-type (147) complexes with N-heteroarylmethyl, N’-mesityl NHCs.
Figure 28: Hoveyda-type complexes 148 and 149 with N-phenylpyrrole, N’-mesityl NHCs.
Figure 29: Grubbs-type complexes with N-trifluoromethyl benzimidazolidene NHCs 150–153, 155 and N-isopropyl be...
Scheme 13: Ethenolysis of ethyl oleate 156.
Scheme 14: Ethenolysis of cis-cyclooctene (47).
Figure 30: Grubbs-type C1-symmetric (164) and C2-symmetric (165) catalysts with a backbone-substituted NHC.
Figure 31: Possible syn and anti rotational isomers of catalyst 164.
Scheme 15: ARCM of substrates 166, 168 and 170.
Figure 32: Hoveyda (172) and Grubbs-type (173,174) backbone-substituted C1-symmetric NHC complexes.
Scheme 16: ARCM of 175,177 and 179 with catalyst 174.
Figure 33: Grubbs-type C1-symmetric NHC catalysts bearing N-propyl (181, 182) or N-benzyl (183, 184) groups on...
Scheme 17: ARCM of 185 and 187 promoted by 184 to form the encumbered alkenes 186 and 188.
Figure 34: N-Alkyl, N’-isopropylphenyl NHC ruthenium complexes with syn (189, 191) and anti (190, 192) phenyl ...
Figure 35: Hoveyda-type complexes 193–198 bearing N-alkyl, N’-aryl backbone-substituted NHC ligands.
Scheme 18: ARCM of 166 and 199 promoted by 192b.
Figure 36: Enantiopure catalysts 201a and 201b with syn phenyl units on the NHC backbone.
Figure 37: Backbone-monosubstituted catalysts 202–204.
Figure 38: Grubbs (205a) and Hoveyda-type (205b) backbone-monosubstituted catalysts.
Scheme 19: AROCM of 206 with allyltrimethylsilane promoted by catalyst 205a.
Efficient catalytic alkyne metathesis with a fluoroalkoxy-supported ditungsten(III) complex
- Henrike Ehrhorn,
- Janin Schlösser,
- Dirk Bockfeld and
- Matthias Tamm
Beilstein J. Org. Chem. 2018, 14, 2425–2434, doi:10.3762/bjoc.14.220
- molybdenum propylidyne precursors to form chelate complexes of type IV [31][32][33][34]. These catalysts were especially successful in the construction of supramolecular materials such as ethynylene-linked polymers [11][35], porous networks [36] and molecular cages [37][38][39][40][41][42][43]. Furthermore
Graphical Abstract
Figure 1: Selected homogeneous catalysts for alkyne metathesis.
Scheme 1: Synthesis of alkylidyne complex V from bimetallic [(t-BuO)3W≡W(Ot-Bu)3]; the catalytically active d...
Scheme 2: Synthesis of hexakis(fluoroalkoxide) dimers Mo2F6 [73] and W2F3.
Figure 2: Molecular structure of W2F3·NHMe2 with thermal displacement parameters drawn at 50% probability. Hy...
Scheme 3: Preparation of the alkylidyne complex WPhF3.
Figure 3: Molecular structure of WPhF3 with thermal displacement parameters drawn at 50% probability. Hydroge...
Scheme 4: Self-metathesis of 1-phenyl-1-propyne derivatives by tungsten complexes W2F3 and WPhF3.
Figure 4: Conversion versus time diagram for the self-metathesis of 1-phenyl-1-propyne catalyzed by 0.5 mol % ...
Fe(II)/Et3N-Relay-catalyzed domino reaction of isoxazoles with imidazolium salts in the synthesis of methyl 4-imidazolylpyrrole-2-carboxylates, its ylide and betaine derivatives
- Ekaterina E. Galenko,
- Olesya A. Tomashenko,
- Alexander F. Khlebnikov,
- Mikhail S. Novikov and
- Taras L. Panikorovskii
Beilstein J. Org. Chem. 2015, 11, 1732–1740, doi:10.3762/bjoc.11.189
- ] and many papers were published recently [15][16][17][18][19][20][21][22]. The 4–6 triads could particularly be interesting as new ligands for the preparation of mixed complexes: a chelate complex with the carboxypyrrole part and a monodentate NHC complex. Not so much is known about metal chelate
- complexes of pyrrole-2-carboxylic acid [23][24][25]. In some cases these complexes were prepared via dehydration of the corresponding proline complexes [25]. Substituted pyrrole-2-carboxylic acids as ligands of complexes are seldom used and are only exemplified by complexes of indole-2-carboxylic acid [26
Graphical Abstract
Scheme 1: The formation and possible tautomeric equilibria of 2-methoxycarbonyl- and 2-carboxy-3-(1H-imidazol...
Scheme 2: FeCl2/Et3N-catalyzed domino sequence leading to 5-alkoxycarbonylpyrrol-3-ylimidazolium salts 1.
Scheme 3: The synthesis of methyl 4-(1H-imidazol-1-yl)-1H-pyrrole-2-carboxylates 12.
Scheme 4: The hydrolysis of ylide 2a and bromide 1b.
Figure 1: Molecular structure of compound 6b (CCDC 1406417). Carbon, nitrogen and oxygen atoms are grey, blue...
Adsorption mechanism and valency of catechol-functionalized hyperbranched polyglycerols
- Stefanie Krysiak,
- Qiang Wei,
- Klaus Rischka,
- Andreas Hartwig,
- Rainer Haag and
- Thorsten Hugel
Beilstein J. Org. Chem. 2015, 11, 828–836, doi:10.3762/bjoc.11.92
- reduced state [5][9]. The byssal plaque also shows strong cohesion through crosslinks. The cysteins can crosslink with DOPA and the oxidized DOPA (semiquinones) can crosslink via radical addition. Furthermore, crosslinking by iron chelate complexes of DOPA improves cohesion [10]. The adhesion of a single
Graphical Abstract
Figure 1: A) A maximum rupture force (max force) histogram for a dopamine-functionalized tip is given for the...
Figure 2: A) Maximum force histograms for the different dwell times indicated in the inset normalized to the ...
Figure 3: Schematics of the different possibilities for attachment via multiple catechols. A) Multivalent att...
Figure 4: A) Force–distance curves where the rupture is not smooth but rather interrupted by a cluster of mea...
Host–guest-driven color change in water: influence of cyclodextrin on the structure of a copper complex of poly((4-hydroxy-3-(pyridin-3-yldiazenyl)phenethyl)methacrylamide-co-dimethylacrylamide)
- Nils Retzmann,
- Gero Maatz and
- Helmut Ritter
Beilstein J. Org. Chem. 2014, 10, 2480–2483, doi:10.3762/bjoc.10.259
- studied extensively, causing for example a blue to red color transition of polydiacetylenes (PDAS) due to the formation of inclusion complexes [6][7]. Azo dyes, with their remarkable ability to form stable azo–metal chelate complexes with outstanding thermal and optical properties have been studied widely
- and led to an increased usage of dyes in the field of optical recording media [8][9]. However, up to now, only little is known about the interactions of azo–metal chelate complexes in supramolecular structures with CD as a modulator for macromolecular effects. Few reports dealt with the reversibility
Graphical Abstract
Scheme 1: Synthesis of N-(4-hydroxy-3-(pyridin-3-yldiazenyl)phenethyl) methacrylamide (5) and preparation of ...
Figure 1: Color-changing effects of polymer 7 upon addition of A) CuSO4 and B) CuSO4 and γ-CD in a 50:50 vol ...
Figure 2: UV–vis absorption spectra of (orange) the solved copolymer 7 with the induced shifts by addition of...
Figure 3: Number average particle size distribution of 7 obtained by DLS experiments.
Advancements in the mechanistic understanding of the copper-catalyzed azide–alkyne cycloaddition
- Regina Berg and
- Bernd F. Straub
Beilstein J. Org. Chem. 2013, 9, 2715–2750, doi:10.3762/bjoc.9.308
Graphical Abstract
Scheme 1: Exemplary 1,3-dipolar cycloaddition of phenylacetylene with phenyl azide [6].
Scheme 2: CuAAC reaction of benzyl azide with (prop-2-yn-1-yloxy)benzene [12].
Scheme 3: Bioconjugation reaction of capsid-bound azide groups with alkynyl-functionalized dye molecules (cow...
Figure 1: Tris(triazolylmethyl)amine ligands for CuAAC applications in bioorganic chemistry: TBTA = tris[(1-b...
Figure 2: Derivatives of 2,2’-bipyridine and 1,10-phenanthroline, commonly used ligands in CuAAC reactions un...
Scheme 4: CuAAC reaction with copper(II) precursor salt and rate-accelerating monodentate phosphoramidite lig...
Scheme 5: Synthesis of 1-(adamant-1-yl)-1H-1,2,3-triazol-4-ylcarbonyl-Phe-Gly-OH by solid-supported Click cat...
Scheme 6: CuAAC reaction with re-usable copper(I)-tren catalyst [129].
Scheme 7: CuAAC test reaction with chlorido[tris(1-benzyl-1H-1,2,3-triazol-4-yl)methanol-κ3N3]copper(I) and a...
Scheme 8: CuAAC model reaction with [Cu2(μ-TBTA-κ4N2,N3,N3’,N3’’)2][BF4]2 [131].
Scheme 9: Application of a (2-aminoarenethiolato)copper(I) complex as homogeneous catalyst for the CuAAC test...
Scheme 10: Application of [CuBr(PPh3)3] as homogeneous catalyst for the CuAAC test reaction of benzyl azide wi...
Figure 3: Phosphinite and phosphonite copper(I) complexes presented by Díez-González [144].
Scheme 11: Effect of additives on the CuAAC test reaction with [(SIMes)CuCl] [149].
Scheme 12: Initiation of the catalytic cycle by formation of the copper acetylide intermediate from [(ICy)2Cu]...
Scheme 13: Early mechanistic proposal by Sharpless [12,42].
Scheme 14: Chemoselective synthesis of a 5-iodo-1,4-disubstituted 1,2,3-triazole [156].
Scheme 15: Mechanistic proposals for the copper-catalyzed azide–iodoalkyne cycloaddition [156].
Scheme 16: 1,3-Dipolar cycloaddition of 3-hexyne catalyzed by [(SIMes)CuBr] [146].
Scheme 17: Mechanistic picture for the cycloaddition of internal alkynes catalyzed by NHC-copper(I) complexes ...
Scheme 18: Catalytic cycle of the CuAAC reaction on the basis of the proposed mechanistic scheme by Fokin and ...
Figure 4: Schematic representation of the single crystal X-ray structures of copper(I) acetylide complexes [Cu...
Figure 5: Acetylide-bridged dicopper complexes with tris(heteroarylmethyl)amine ligand(s) as key intermediate...
Scheme 19: Off-cycle equilibrium between unreactive polymeric copper(I) acetylide species (right) and reactive...
Figure 6: Categories of tris(heteroarylmethyl)amine ligands regarding their binding ability to copper(I) ions ...
Scheme 20: Mechanistic scheme for ligand-accelerated catalysis with tripodal tris(heteroarylmethyl)amine ligan...
Scheme 21: Synthesis of supposed intermediates in the CuAAC’s catalytic cycle [164,187].
Figure 7: Tetranuclear copper acetylide complexes as reported by Weiss (left) [176] and Tasker (middle) [185] and model...
Figure 8: Gibbs free energy diagram for the computed mechanistic pathway of the CuAAC reaction starting from ...
Figure 9: Energy diagram by Ahlquist and Fokin [125].
Scheme 22: Mechanistic proposal for the CuAAC reaction based on DFT calculations by Fokin [125] and our group [186] ([Cu...
Figure 10: ORTEP plot [202,203] of the X-ray powder diffraction crystal structure of (phenylethynyl)copper(I) [(PhC≡CCu)...
Scheme 23: Synthesis of [(PhC≡CCu)2]n as co-product in the Glaser coupling of phenylacetylene in the presence ...
Scheme 24: Mechanistic explanation for the isotopic enrichment in the product triazolide in the presence of th...
Scheme 25: Homogeneous CuAAC catalysis with a bistriazolylidene dicopper complex (0.5 mol %) and comparison wi...
Syntheses and applications of furanyl-functionalised 2,2’:6’,2’’-terpyridines
- Jérôme Husson and
- Michael Knorr
Beilstein J. Org. Chem. 2012, 8, 379–389, doi:10.3762/bjoc.8.41
- , medicinal chemistry and material sciences. Keywords: chelate complexes; furan; heterocycles; oligopyridines; terpyridine; Introduction Since their discovery [1][2] in the 1930s, 2,2’:6’,2’’-terpyridines (tpy) (Figure 1) have attracted widespread attention because of their excellent complexing properties
Graphical Abstract
Figure 1: Structure and atomic numbering of 2,2’:6’,2’’-terpyridines.
Scheme 1: Synthesis of furanyl-substituted terpyridines 12–14 by using Kröhnke’s method.
Scheme 2: Synthesis of terpyridines under solvent-free conditions.
Scheme 3: Preparation of 4,4′,4′′-trisubstituted terpyridine containing carboxylate moieties.
Scheme 4: Synthetic pathway for the preparation of a furanyl-functionalised quinquepyridine.
Scheme 5: Utilization of an iminium salt in the preparation of a furanyl-substituted tpy.
Figure 2: Chemical structure of U- and S-shaped isomers.
Scheme 6: Preparation of an asymmetric furanyl-substituted terpyridine.
Scheme 7: Synthesis of tpy by Stille cross-coupling reaction.
Scheme 8: Oxidation of the furan ring of furanyl-substituted terpyridines.
Scheme 9: Direct oxidation of a furan ring attached on Ru(II) tpy complexes.
Figure 3: Example of polyoxometalate frameworks functionalised with tpy ligands and tpy-complex (reprinted wi...
Scheme 10: Synthetic pathway to europium(III) and samarium(III) chelates 56 and 57.
Scheme 11: Synthetic pathway to prepare thiocyanato-functionalised tpys as potential biomolecule-labelling age...
Scheme 12: Synthetic sequence envisioned for biomolecules labelling by click-chemistry.
Figure 4: Structure of pyrrolyl (66), thienyl (67) and bithienyl (68)-substituted complexes analogous to comp...
An overview of the key routes to the best selling 5-membered ring heterocyclic pharmaceuticals
- Marcus Baumann,
- Ian R. Baxendale,
- Steven V. Ley and
- Nikzad Nikbin
Beilstein J. Org. Chem. 2011, 7, 442–495, doi:10.3762/bjoc.7.57
Graphical Abstract
Figure 1: Structures of atorvastatin and other commercial statins.
Figure 2: Structure of compactin.
Scheme 1: Synthesis of pentasubstituted pyrroles.
Scheme 2: [3 + 2] Cycloaddition to prepare 5-isopropylpyrroles.
Scheme 3: Regiospecific [3 + 2] cycloaddition to prepare the pyrrole scaffold.
Scheme 4: Formation of the pyrrole core of atorvastatin via [3 + 2] cycloaddition.
Scheme 5: Formation of pyrrole 33 via the Paal–Knorr reaction.
Scheme 6: Convergent synthesis towards atorvastatin.
Figure 3: Binding pocket of sunitinib in the TRK KIT.
Scheme 7: Synthesis of sunitinib.
Scheme 8: Alternative synthesis of sunitinib.
Scheme 9: Key steps in the syntheses of sumatriptan and zolmitriptan.
Scheme 10: Introduction of the N,N-dimethylaminoethyl side chain.
Scheme 11: Japp–Klingemann reaction in the synthesis of sumatriptan.
Scheme 12: Synthesis of the intermediate sulfonyl chlorides 62 and 63.
Scheme 13: Alternative introduction of the sulfonamide.
Scheme 14: Negishi-type coupling to benzylic sulfonamides.
Scheme 15: Heck reaction used to introduce the sulfonamide side chain of naratriptan.
Scheme 16: Synthesis of the oxazolinone appendage of zolmitriptan.
Scheme 17: Grandberg indole synthesis used in the preparation of rizatriptan.
Scheme 18: Improved synthesis of rizatriptan.
Scheme 19: Larock-type synthesis of rizatriptan.
Scheme 20: Synthesis of eletriptan.
Scheme 21: Heck coupling for the indole system in eletriptan.
Scheme 22: Attempted Fischer indole synthesis of elatriptan.
Scheme 23: Successful Fischer indole synthesis for eletriptan.
Scheme 24: Mechanistic rationale for the Bischler–Möhlau reaction.
Scheme 25: Bischler-type indole synthesis used in the fluvastatin sodium synthesis.
Scheme 26: Palladium-mediated synthesis of ondansetron.
Scheme 27: Fischer indole synthesis of ondansetron.
Scheme 28: Optimised Pictet–Spengler reaction towards tadalafil.
Figure 4: Structures of carvedilol 136 and propranolol 137.
Scheme 29: Synthesis of the carbazole core of carvedilol.
Scheme 30: Alternative syntheses of 4-hydroxy-9H-carbazole.
Scheme 31: Convergent synthesis of etodolac.
Scheme 32: Alternative synthesis of etodolac.
Figure 5: Structures of imidazole-containing drugs.
Scheme 33: Synthesis of functionalised imidazoles towards losartan.
Scheme 34: Direct synthesis of the chlorinated imidazole in losartan.
Scheme 35: Synthesis of trisubstituted imidazoles.
Scheme 36: Preparation of the imidazole ring in olmesartan.
Scheme 37: Synthesis of ondansetron.
Scheme 38: Alternative route to ondansetron and its analogues.
Scheme 39: Proton pump inhibitors and synthesis of esomeprazole.
Scheme 40: Synthesis of benzimidazole core pantoprazole.
Figure 6: Structure of rabeprazole 194.
Scheme 41: Synthesis of candesartan.
Scheme 42: Alternative access to the candesartan key intermediate 216.
Scheme 43: .Medicinal chemistry route to telmisartan.
Scheme 44: Improved synthesis of telmisartan.
Scheme 45: Synthesis of zolpidem.
Scheme 46: Copper-catalysed 3-component coupling towards zolpidem.
Figure 7: Structure of celecoxib.
Scheme 47: Preparation of celecoxib.
Scheme 48: Alternative synthesis of celecoxib.
Scheme 49: Regioselective access to celecoxib.
Scheme 50: Synthesis of pazopanib.
Scheme 51: Syntheses of anastrozole, rizatriptan and letrozole.
Scheme 52: Regioselective synthesis of anastrozole.
Scheme 53: Triazine-mediated triazole formation towards anastrozole.
Scheme 54: Alternative routes to 1,2,4-triazoles.
Scheme 55: Initial synthetic route to sitagliptin.
Figure 8: Binding of sitagliptin within DPP-IV.
Scheme 56: The process route to sitagliptin key intermediate 280.
Scheme 57: Synthesis of maraviroc.
Scheme 58: Synthesis of alprazolam.
Scheme 59: The use of N-nitrosoamidine derivatives in the preparation of fused benzodiazepines.
Figure 9: Structures of itraconazole, ravuconazole and voriconazole.
Scheme 60: Synthesis of itraconazole.
Scheme 61: Synthesis of rufinamide.
Scheme 62: Representative tetrazole formation in valsartan.
Figure 10: Structure of tetrazole containing olmesartan, candesartan and irbesartan.
Scheme 63: Early stage introduction of the tetrazole in losartan.
Scheme 64: Synthesis of cilostazol.
Figure 11: Structure of cefdinir.
Scheme 65: Semi-synthesis of cefdinir.
Scheme 66: Thiazole syntheses towards ritonavir.
Scheme 67: Synthesis towards pramipexole.
Scheme 68: Alternative route to pramipexole.
Scheme 69: Synthesis of famotidine.
Scheme 70: Efficient synthesis of the hyperuricemic febuxostat.
Scheme 71: Synthesis of ziprasidone.
Figure 12: Structure of mometasone.
Scheme 72: Industrial access to 2-furoic acid present in mometasone.
Scheme 73: Synthesis of ranitidine from furfuryl alcohol.
Scheme 74: Synthesis of nitrofurantoin.
Scheme 75: Synthesis of benzofuran.
Scheme 76: Synthesis of amiodarone.
Scheme 77: Synthesis of raloxifene.
Scheme 78: Alternative access to the benzo[b]thiophene core of raloxifene.
Scheme 79: Gewald reaction in the synthesis of olanzapine.
Scheme 80: Alternative synthesis of olanzapine.
Figure 13: Access to simple thiophene-containing drugs.
Scheme 81: Synthesis of clopidogrel.
Scheme 82: Pictet–Spengler reaction in the preparation of tetrahydrothieno[3,2-c]pyridine (422).
Scheme 83: Alternative synthesis of key intermediate 422.
Figure 14: Co-crystal structures of timolol (left) and carazolol (right) in the β-adrenergic receptor.
Scheme 84: Synthesis of timolol.
Scheme 85: Synthesis of tizanidine 440.
Scheme 86: Synthesis of leflunomide.
Scheme 87: Synthesis of sulfamethoxazole.
Scheme 88: Synthesis of risperidone.
Figure 15: Relative abundance of selected transformations.
Figure 16: The abundance of heterocycles within top 200 drugs (5-membered rings).
A superior P-H phosphonite: Asymmetric allylic substitutions with fenchol- based palladium catalysts
- Bernd Goldfuss,
- Thomas Löschmann,
- Tina Kop-Weiershausen,
- Jörg Neudörfl and
- Frank Rominger
Beilstein J. Org. Chem. 2006, 2, No. 7, doi:10.1186/1860-5397-2-7
- computational transition structure analyses, these phenyl and anisyl phosphinites are not "monodentate" but form chelate complexes via π-coordination. Biphenyl-2,2'-bisfenchol (BIFOL)[13] was developed as combination of a flexible biaryl axis (as in BINOL) and sterically crowded hydroxy groups (as in TADDOLs
Graphical Abstract
Scheme 1: Pd-catalyzed allylic substitution with unsymmetrical substrates (Nu = dimethylmalonate, Nf = OAc).
Scheme 2: Bidentate P, N-ligands and a monodentate phosphoramidite for Pd-catalyzed allylic substitutions wit...
Scheme 3: Fenchole-based phosphorus ligands (i.e. FEENOPs and BIFOPs) for Pd-catalyzed allylic substitutions....
Scheme 4: Allylic alkylation of 1-phenyl-2-propenyl acetate by sodium dimethylmalonate (BSA-method) with Pd-F...
Figure 1: X-ray crystal structure of the cationic complex Pd-FENOP (CCDC 299944), the perchlorate counterion ...
Figure 2: X-ray crystal structure of the cationic complex Pd-FENOP-Me (CCDC 600369), the perchlorate counteri...
Figure 3: X-ray crystal structure of the cationic complex Pd-FENOP-NMe2 (CCDC 600370), the perchlorate counte...
Figure 4: The two most stable ONIOM(B3LYP/SDD(+ECP) (Pd) /6-31G* (C, H, O, N, P) : UFF) optimized transition ...
Figure 5: The two most stable ONIOM(B3LYP/SDD(+ECP) (Pd) /6-31G* (C, H, O, N, P) : UFF) optimized transition ...
