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Search for "pyrroloindoles" in Full Text gives 4 result(s) in Beilstein Journal of Organic Chemistry.
Highly selective Diels–Alder and Heck arylation reactions in a divergent synthesis of isoindolo- and pyrrolo-fused polycyclic indoles from 2-formylpyrrole
- Carlos H. Escalante,
- Eder I. Martínez-Mora,
- Carlos Espinoza-Hicks,
- Alejandro A. Camacho-Dávila,
- Fernando R. Ramos-Morales,
- Francisco Delgado and
- Joaquín Tamariz
Beilstein J. Org. Chem. 2020, 16, 1320–1334, doi:10.3762/bjoc.16.113
- in governing the endo stereocontrol. Keywords: endo-Diels–Alder stereocontrol; 2-formylpyrrole; intramolecular Heck arylation reaction; non-covalent interactions; pyrroloindoles; pyrroloisoindoles; Introduction Pyrrolizines [1][2] and pyrrolizidines [3][4], abundant in nature [4][5], are among the
Graphical Abstract
Figure 1: Fused aza-hetero polycyclic frames and natural pyrrolizine- and isoindole-containing alkaloids.
Scheme 1: Synthetic approaches for the preparation of pyrrolo-fused aza-hetero polycyclic frames.
Scheme 2: Preparation of 1,2-substituted pyrroles 8a–f and 8i,j.
Scheme 3: Diels–Alder cycloadditions of pyrroles 8a–j and 16a–b with maleimides 7b–c.
Figure 2: Structures of 9m (a) and 10m (b) as determined by single-crystal X-ray diffraction crystallography ...
Scheme 4: Pd(0)-catalyzed intramolecular Heck cross-coupling reaction of 2-vinylpyrroles 8c,d and 8g.
Scheme 5: Synthesis of 2-vinylpyrroles 8k,l and their Pd(0)-catalyzed intramolecular Heck cross-coupling to p...
Scheme 6: Diastereoselective Diels–Alder reaction of pyrrolo[2,1-a]isoindole 18a with 7c.
Scheme 7: Synthetic approach to the fused aza-heterocyclic pentacycle 12.
Figure 3: M06-2X/6-31+G(d,p) Optimized geometry for each of the SCs (a and d), TSs (b and e) and ADs (c and f...
Figure 4: M06-2X/6-31+G(d,p) Optimized geometry for each of the TSs of the Diels–Alder reactions of dienes 8b...
Figure 5: M06-2X/6-31+G(d,p) Optimized geometry of the endo SCs (a) and TSs (b) for the Diels–Alder reaction ...
Simple synthesis of pyrrolo[3,2-e]indole-1-carbonitriles
- Adam Trawczyński,
- Robert Bujok,
- Zbigniew Wróbel and
- Krzysztof Wojciechowski
Beilstein J. Org. Chem. 2013, 9, 934–941, doi:10.3762/bjoc.9.107
- removed by a procedure elaborated by us [18] employing α-bromoacetophenone in the presence of triethylamine as exemplified for pyrroloindoles 6a and 6d that were transformed under these conditions into the corresponding derivatives 8a and 8d (Scheme 2). The crude 3-hydroxy-pyrrolo[3,2-e]indole 6d without
Graphical Abstract
Scheme 1: Synthesis of pyrrolo[3,2-e]indoles via VNS in 5-nitroindoles [6,12].
Scheme 2: Synthesis of pyrrolo[3,2-e]indoles 6.
Scheme 3: Plausible route for transformation of indoles 5 into pyrrolo[3,2-e]indoles 6.
Scheme 4: Removal of the benzyloxymethyl group from the compound 8a.
A review of new developments in the Friedel–Crafts alkylation – From green chemistry to asymmetric catalysis
- Magnus Rueping and
- Boris J. Nachtsheim
Beilstein J. Org. Chem. 2010, 6, No. 6, doi:10.3762/bjoc.6.6
- of indole. Pd-catalyzed synthesis of pyrroloindoles from L-tryptophane. Ru(IV)-catalyzed allylation of indole and pyrroles with unique regioselectivity. Silver(I)-catalyzed intramolecular FC-type allylation of arenes and heteroarenes. FC-type alkylations of arenes using propargyl alcohols. (A
Graphical Abstract
Scheme 1: AlCl3-mediated reaction between amyl chloride and benzene as developed by Friedel and Crafts.
Figure 1: Most often used metal salts for catalytic FC alkylations and hydroarylations of arenes.
Figure 2: 1,1-diarylalkanes with biological activity.
Scheme 2: Alkylating reagents and side products produced.
Scheme 3: Initially reported TeCl4-mediated FC alkylation of 1-penylethanol with toluene.
Scheme 4: Sc(OTf)3-catalyzed FC benzylation of arenes.
Scheme 5: Reductive FC alkylation of arenes with arenecarbaldehydes.
Scheme 6: Iron(III)-catalyzed FC benzylation of arenes and heteroarenes.
Scheme 7: A gold(III)-catalyzed route to beclobrate.
Scheme 8: Catalytic FC-type alkylations of 1,3-dicarbonyl compounds.
Scheme 9: Iron(III)-catalyzed synthesis of phenprocoumon.
Scheme 10: Bi(OTf)3-catalyzed FC alkylation of benzyl alcohols developed by Rueping et al.
Scheme 11: (A) Bi(OTf)3-catalyzed intramolecular FC alkylation as an efficient route to substituted fulvenes. ...
Scheme 12: FC-type glycosylation of 1,2-dimethylindole and trimethoxybenzene.
Scheme 13: FC alkylation with highly reactive ferrocenyl- and benzyl alcohols. The reaction proceeds even with...
Scheme 14: Reductive FC alkylation of arenes with benzaldehyde and acetophenone catalyzed by the Ir-carbene co...
Scheme 15: Formal synthesis of 1,1-diarylalkanes from benzyl alcohols and styrenes.
Scheme 16: (A) Mo-catalyzed hydroarylation of styrenes and cyclohexenes. (B) Hydroalkylation–cyclization casca...
Scheme 17: Bi(III)-catalyzed hydroarylation of styrenes with arenes and heteroarenes.
Scheme 18: BiCl3-catalyzed ene/FC alkylation reaction cascade – A fast access to highly arylated dihydroindene...
Scheme 19: Au(I)/Ag(I)-catalyzed hydroarylation of indoles with styrenes, aliphatic and cyclic alkenes.
Scheme 20: First transition-metal-catalyzed ortho-hydroarylation developed by Beller et al.
Scheme 21: (A) Ti(IV)-mediated rearrangement of an N-benzylated aniline to the corresponding ortho-alkylated a...
Scheme 22: Dibenzylation of aniline gives potentially useful amine-based ligands in a one-step procedure.
Scheme 23: FC-type alkylations with allyl alcohols as alkylating reagents – linear vs. branched product format...
Scheme 24: (A) First catalytic FC allylation and cinnamylation using allyl alcohols and its derivatives. (B) E...
Scheme 25: FC allylation/cyclization reaction yielding substituted chromanes.
Scheme 26: Synthesis of (all-rac)-α-tocopherol utilizing Lewis- and strong Brønsted-acids.
Scheme 27: Au(III)-catalyzed cinnamylation of arenes.
Scheme 28: “Exhaustive” allylation of benzene-1,3,5-triol.
Scheme 29: Palladium-catalyzed allylation of indole.
Scheme 30: Pd-catalyzed synthesis of pyrroloindoles from L-tryptophane.
Scheme 31: Ru(IV)-catalyzed allylation of indole and pyrroles with unique regioselectivity.
Scheme 32: Silver(I)-catalyzed intramolecular FC-type allylation of arenes and heteroarenes.
Scheme 33: FC-type alkylations of arenes using propargyl alcohols.
Scheme 34: (A) Propargylation of arenes with stoichiometric amounts of the Ru-allenylidene complex 86. (B) Fir...
Scheme 35: Diruthenium-catalyzed formation of chromenes and 1H-naphtho[2,1-b]pyrans.
Scheme 36: Rhenium(V)-catalyzed FC propargylations as a first step in the total synthesis of podophyllotoxin, ...
Scheme 37: Scandium-catalyzed arylation of 3-sulfanyl- and 3-selanylpropargyl alcohols.
Scheme 38: Synthesis of 1,3-diarylpropynes via direct coupling of propargyl trichloracetimidates and arenes.
Scheme 39: Diastereoselective substitutions of benzyl alcohols.
Scheme 40: (A) First diastereoselective FC alkylations developed by Bach et al. (B) anti-Selective FC alkylati...
Scheme 41: Diastereoselective AuCl3-catalyzed FC alkylation.
Scheme 42: Bi(OTf)3-catalyzed alkylation of α-chiral benzyl acetates with silyl enol ethers.
Scheme 43: Bi(OTf)3-catalyzed diastereoselective substitution of propargyl acetates.
Scheme 44: Nucelophilic substitution of enantioenriched ferrocenyl alcohols.
Scheme 45: First catalytic enantioselective propargylation of arenes.
Mitomycins syntheses: a recent update
- Jean-Christophe Andrez
Beilstein J. Org. Chem. 2009, 5, No. 33, doi:10.3762/bjoc.5.33
Graphical Abstract
Scheme 1: Aziridine containing natural products.
Scheme 2: Mitomycin structures and nomenclature.
Scheme 3: Base catalysed epimerization of mitomycin B.
Scheme 4: Biosynthesis of mitomycin C (MMC) 7.
Scheme 5: Mode of action of mitomycin C.
Scheme 6: The N–C3–C9a disconnection.
Scheme 7: Danishefsky’s Retrosynthesis of mitomycin K.
Scheme 8: Hetero Diels–Alder reaction en route to mitomycins.
Scheme 9: Nitroso Diels–Alder cycloaddition.
Scheme 10: Frank azide cycloadddition.
Scheme 11: Final steps of mitomycin K synthesis. aPDC, DCM; bPhSCH2N3, PhH, 80 °C; cL-selectride, THF, −78 °C; ...
Scheme 12: Naruta–Maruyama retrosynthesis.
Scheme 13: Synthesis of a leucoaziridinomitosane by nitrene cycloaddition. aAlCl3-Et2O; bNaH, ClCH2OMe; cn-BuL...
Scheme 14: Thermal decomposition of azidoquinone 51.
Scheme 15: Diastereoselectivity during the cycloaddition.
Scheme 16: Oxidation with iodo-azide.
Scheme 17: Williams’ approach towards mitomycins.aDEIPSCl, Imidazole, DCM; bPd/C, HCO2NH4, MeOH; cAllocCl, NaH...
Scheme 18: Synthesis of pyrrolidones by homoconjugate addition.
Scheme 19: Homoconjugate addition on the fully functionalized substrate.
Scheme 20: Introduction of the olefin.
Scheme 21: Retrosynthesis of N–C9a, N–C3 bond formation.
Scheme 22: Synthesis of the pyrrolo[1,2]indole 82 using N-PSP activation.aAc2O, Py; bAc2O, Hg(OAc)2, AcOH, 90%...
Scheme 23: Synthesis of an aziridinomitosane. am-CPBA, DCM then iPr2NH, CCl4 reflux; bK2CO3, MeOH; cBnBr, KH; d...
Scheme 24: Oxidation products of a leucoaziridinomitosane obtained from a Polonovski oxidation.
Scheme 25: Polonovski oxidation of an aziridinomitosane. am-CPBA; bPd/C, H2; cDimethoxypropane, PPTS.
Scheme 26: The C1–C9a disconnection.
Scheme 27: Ziegler synthesis of desmethoxymitomycin A.aIm2C=O, THF; bNH3; cTMSOTf, 2,6-di-tert-butylpyridine, ...
Scheme 28: Transformation of sodium erythorbate.aTBDMSCl; bNaN3; cPPh3; d(Boc)2O, DMAP; eTBAF; fTf2O, Pyr.
Scheme 29: Formation of C9,C10-unsaturation in the mitomycins. am-CPBA, DCM; bO3, MeOH; cMe2S; dKHMDS, (EtO)3P...
Scheme 30: Fragmentation mechanism.
Scheme 31: Michael addition-cyclisation.
Scheme 32: SmI2 8-endo-dig cyclisation.
Scheme 33: Synthesis of pyrrolo[1,2-a]indole by 5-exo-dig radical cyclization.
Scheme 34: The C9–C9a disconnection.
Scheme 35: Intramolecular nitrile oxide cycloaddition.
Scheme 36: Regioselectivity of the INOC.
Scheme 37: Fukuyama’s INOC strategy.
Scheme 38: Synthesis of a mitosane core by rearrangement of a 1-(1-pyrrolidinyl)-1,3-butadiene.
Scheme 39: Sulikowski synthesis of an aziridinomitosene. aPd(Tol3P)2Cl2, Bu3SnF, 140; bH2, Pd/C; cTFAA, Et3N; d...
Scheme 40: Enantioselective carbene insertion.
Scheme 41: Parson’s radical cyclization.
Scheme 42: Cha’s mitomycin B core synthesis.
Scheme 43: The N-aromatic disconnection.
Scheme 44: Kishi retrosynthesis.
Scheme 45: Kishi synthesis of a starting material. aallyl bromide, K2CO3, acetone, reflux; bN,N-Dimethylanilin...
Scheme 46: Kishi synthesis of MMC 7. aLDA, THF, −78 °C then PhSeBr, THF, −78 °C; bH2O2, THF-EtOAc; cDIBAL, DCM...
Scheme 47: Acid catalyzed degradation of MMC 7.
Scheme 48: In vivo formation of apomitomycin B.
Scheme 49: Advanced intermediate for apomitomycin B synthesis.
Scheme 50: Remers synthesis of a functionalized mitosene. aTMSCl, Et3N, ZnCl2 then NBS; bAcOK; cNH2OH; dPd/C, H...
Scheme 51: Coleman synthesis of desmethoxymitomycin A. aSnCl2, PhSH, Et3N, CH3CN; bClCO2Bn, Et3N; cPPh3, DIAD,...
Scheme 52: Transition state and pyrrolidine synthesis.
Scheme 53: Air oxidation of mitosanes and aziridinomitosanes.
Scheme 54: The C9-aromatic disconnection.
Scheme 55: Synthesis of the aziridine precursor. aLHMDS, THF; bNaOH; c(s)-α-Me-BnNH2, DCC, HOBT; dDIBAL; eK2CO3...
Scheme 56: Synthesis of 206 via enamine conjugate addition.
Scheme 57: Rapoport synthesis of an aziridinomitosene.
Scheme 58: One pot synthesis of a mitomycin analog.
Scheme 59: Synthesis of compound 218 via intramolecular Heck coupling. aEtMgCl, THF, then 220; bMsCl, Et3N; cN...
Scheme 60: Elaboration of indole 223. aEt3N, Ac2O; bAcOH; cSOCl2, Et3N; dNaN3, DMF; eH2SO4, THF; fK2CO3, MeOH; ...
Scheme 61: C9-C9a functionalization from indole.
Scheme 62: Synthesis of mitomycin K. a2 equiv. MoO5.HMPA, MeOH; bPPh3, Et3N, THF-H2O; cMeOTf, Py, DCM; dMe3SiCH...
Scheme 63: Configurational stability of mitomycin K derivatives.
Scheme 64: Epimerization of carbon C9a in compound 227b.
Scheme 65: Corey–Chaykovsky synthesis of indol 235.
Scheme 66: Cory intramolecular aza-Darzens reaction for the formation of aziridinomitosene 239.
Scheme 67: Jimenez synthesis of aziridinomitosene 242.
Scheme 68: Von Braun opening of indoline 244.
Scheme 69: C9a oxidation of an aziridinomitosane with DDQ/OsO4.
Scheme 70: Synthesis of epi-mitomycin K. aNaH, Me2SO4; bH2, Pd/C; cMitscher reagent [165]; d[(trimethylsilyl)methyl...
Scheme 71: Mitomycins rearrangement.
Scheme 72: Fukuyama’s retrosynthesis.
Scheme 73: [2+3] Cycloaddition en route to isomitomycin A. aToluene, 110 °C; bDIBAL, THF, −78 °C; cAc2O, Py.; d...
Scheme 74: Final steps of Fukuyama’s synthesis.
Scheme 75: “Crisscross annulation”.
Scheme 76: Synthesis of 274; the 8-membered ring 274 was made using a crisscross annulation. a20% Pd(OH)2/C, H2...
Scheme 77: Conformational analysis of compound 273 and 275.
Scheme 78: Synthesis of a mitomycin analog. aNa2S2O4, H2O, DCM; bBnBr (10 equiv), K2CO3, 18-crown-6 (cat.), TH...
Scheme 79: Vedejs retrosynthesis.
Scheme 80: Formation of the azomethine ylide.
Scheme 81: Vedejs second synthesis of an aziridinomitosene. aDIBAL; bTPAP, NMO; c287; dTBSCl, imidazole.
Scheme 82: Trityl deprotection and new aziridine protecting group 300.
Scheme 83: Ene reaction towards benzazocinones.
Scheme 84: Benzazocenols via homo-Brook rearrangement.
Scheme 85: Pt-catalyzed [3+2] cycloaddition.
Scheme 86: Carbonylative lactamization entry to benzazocenols. aZn(OTf)2, (+)-N-methylephedrine, Et3N, TMS-ace...
Scheme 87: 8 membered ring formation by RCM. aBOC2O, NaHCO3; bTBSCl, Imidazole, DMF; callyl bromide, NaH, DMF; ...
Scheme 88: Aziridinomitosene synthesis. aTMSN3; bTFA; cPOCl3, DMF; dNaClO2, NaH2PO4, 2-methyl-2-butene; eMeI, ...
Scheme 89: Metathesis from an indole.
Scheme 90: Synthesis of early biosynthetic intermediates of mitomycins.
