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Search for "zirconium complexes" in Full Text gives 3 result(s) in Beilstein Journal of Organic Chemistry.
Pyridine C(sp2)–H bond functionalization under transition-metal and rare earth metal catalysis
- Haritha Sindhe,
- Malladi Mounika Reddy,
- Karthikeyan Rajkumar,
- Akshay Kamble,
- Amardeep Singh,
- Anand Kumar and
- Satyasheel Sharma
Beilstein J. Org. Chem. 2023, 19, 820–863, doi:10.3762/bjoc.19.62
- demonstrated that the reaction in the presence of cationic zirconium complexes derived from zirconium dibenzyl complexes bearing tridentate [ONO]-type amine-bridged bis(phenolato) ligands and [Ph3C][B(C6F5)4] (Scheme 5), gave rise to ortho-selective C–H alkylated pyridines 19 and 21. It was observed that the
Graphical Abstract
Figure 1: Representative examples of bioactive natural products and FDA-approved drugs containing a pyridine ...
Scheme 1: Classical and traditional methods for the synthesis of functionalized pyridines.
Scheme 2: Rare earth metal (Ln)-catalyzed pyridine C–H alkylation.
Scheme 3: Pd-catalyzed C–H alkylation of pyridine N-oxide.
Scheme 4: CuI-catalyzed C–H alkylation of N-iminopyridinium ylides with tosylhydrazones (A) and a plausible r...
Scheme 5: Zirconium complex-catalyzed pyridine C–H alkylation.
Scheme 6: Rare earth metal-catalyzed pyridine C–H alkylation with nonpolar unsaturated substrates.
Scheme 7: Heterobimetallic Rh–Al complex-catalyzed ortho-C–H monoalkylation of pyridines.
Scheme 8: Mono(phosphinoamido)-rare earth complex-catalyzed pyridine C–H alkylation.
Scheme 9: Rhodium-catalyzed pyridine C–H alkylation with acrylates and acrylamides.
Scheme 10: Ni–Al bimetallic system-catalyzed pyridine C–H alkylation.
Scheme 11: Iridium-catalyzed pyridine C–H alkylation.
Scheme 12: para-C(sp2)–H Alkylation of pyridines with alkenes.
Scheme 13: Enantioselective pyridine C–H alkylation.
Scheme 14: Pd-catalyzed C2-olefination of pyridines.
Scheme 15: Ru-catalyzed C-6 (C-2)-propenylation of 2-arylated pyridines.
Scheme 16: C–H addition of allenes to pyridines catalyzed by half-sandwich Sc metal complex.
Scheme 17: Pd-catalyzed stereodivergent synthesis of alkenylated pyridines.
Scheme 18: Pd-catalyzed ligand-promoted selective C3-olefination of pyridines.
Scheme 19: Mono-N-protected amino acids in Pd-catalyzed C3-alkenylation of pyridines.
Scheme 20: Amide-directed and rhodium-catalyzed C3-alkenylation of pyridines.
Scheme 21: Bimetallic Ni–Al-catalyzed para-selective alkenylation of pyridine.
Scheme 22: Arylboronic ester-assisted pyridine direct C–H arylation.
Scheme 23: Pd-catalyzed C–H arylation/benzylation with toluene.
Scheme 24: Pd-catalyzed pyridine C–H arylation with potassium aryl- and heteroaryltrifluoroborates.
Scheme 25: Transient activator strategy in pyridine C–H biarylation.
Scheme 26: Ligand-promoted C3-arylation of pyridine.
Scheme 27: Pd-catalyzed arylation of nicotinic and isonicotinic acids.
Scheme 28: Iron-catalyzed and imine-directed C–H arylation of pyridines.
Scheme 29: Pd–(bipy-6-OH) cooperative system-mediated direct pyridine C3-arylation.
Scheme 30: Pd-catalyzed pyridine N-oxide C–H arylation with heteroarylcarboxylic acids.
Scheme 31: Pd-catalyzed C–H cross-coupling of pyridine N-oxides with five-membered heterocycles.
Scheme 32: Cu-catalyzed dehydrative biaryl coupling of azine(pyridine) N-oxides and oxazoles.
Scheme 33: Rh(III)-catalyzed cross dehydrogenative C3-heteroarylation of pyridines.
Scheme 34: Pd-catalyzed C3-selective arylation of pyridines.
Scheme 35: Rhodium-catalyzed oxidative C–H annulation of pyridines to quinolines.
Scheme 36: Rhodium-catalyzed and NHC-directed C–H annulation of pyridine.
Scheme 37: Ni/NHC-catalyzed regio- and enantioselective C–H cyclization of pyridines.
Scheme 38: Rare earth metal-catalyzed intramolecular C–H cyclization of pyridine to azaindolines.
Scheme 39: Rh-catalyzed alkenylation of bipyridine with terminal silylacetylenes.
Scheme 40: Rollover cyclometallation in Rh-catalyzed pyridine C–H functionalization.
Scheme 41: Rollover pathway in Rh-catalyzed C–H functionalization of N,N,N-tridentate chelating compounds.
Scheme 42: Pd-catalyzed rollover pathway in bipyridine-6-carboxamides C–H arylation.
Scheme 43: Rh-catalyzed C3-acylmethylation of bipyridine-6-carboxamides with sulfoxonium ylides.
Scheme 44: Rh-catalyzed C–H functionalization of bipyridines with alkynes.
Scheme 45: Rh-catalyzed C–H acylmethylation and annulation of bipyridine with sulfoxonium ylides.
Scheme 46: Iridium-catalyzed C4-borylation of pyridines.
Scheme 47: C3-Borylation of pyridines.
Scheme 48: Pd-catalyzed regioselective synthesis of silylated dihydropyridines.
Aluminacyclopentanes in the synthesis of 3-substituted phospholanes and α,ω-bisphospholanes
- Vladimir A. D’yakonov,
- Alevtina L. Makhamatkhanova,
- Rina A. Agliullina,
- Leisan K. Dilmukhametova,
- Tat’yana V. Tyumkina and
- Usein M. Dzhemilev
Beilstein J. Org. Chem. 2016, 12, 406–412, doi:10.3762/bjoc.12.43
- with molybdenum hexacarbonyl. The structure of the complexes was proved by multinuclear 1H, 13C, and 31P spectroscopy. Keywords: aluminacyclopentanes; Dzhemilev reaction; molybdenum complexes; phospholanes; zirconium complexes; Introduction A widely used approach for the synthesis of cyclic
Graphical Abstract
Scheme 1: Synthesis of 3-substituted phospholanes according to earlier data [14-17].
Scheme 2: Synthesis of 3-substituted phospholanes.
Scheme 3: Synthesis of 3-substituted phospholane oxides and sulfides.
Scheme 4: Synthesis of 3-substituted 7a–f and 2-substituted 8a–f phospholanes.
Scheme 5: Synthesis of bisphospholanes.
Scheme 6: Synthesis of bisphospholane-1,1'-oxides and bisphospholane-1,1'-sulfides.
Scheme 7: Synthesis of the molybdenum complex (3-hexyl(benzyl)-1-phenyl(methyl)phospholane)Mo(CO)5.
Scheme 8: Synthesis of molybdenum complexes (1,2(1,6)-bis(1-phenylphospholan-3-yl)ethane(hexane))Mo(CO)5.
Metal–ligand multiple bonds as frustrated Lewis pairs for C–H functionalization
- Matthew T. Whited
Beilstein J. Org. Chem. 2012, 8, 1554–1563, doi:10.3762/bjoc.8.177
- role, as one can envision a bimolecular pathway to acid–base adduct formation (Figure 2a). Such dimerization does occur in cases with insufficient steric encumbrance (e.g., the bis-μ-imido zirconium complexes of Bergman, Figure 2b) [25]. Thus, as for the main-group FLPs of Stephan and others
Graphical Abstract
Scheme 1: Heterolytic cleavage of H2 by a phosphine/borane FLP by H2 polarization in the P–B cavity [5,11].
Scheme 2: Insertion of carbon dioxide into a phosphine/borane FLP [14].
Figure 1: Simplified frontier-molecular-orbital diagrams for (a) Mδ+═Eδ− and (b) Mδ−═Eδ+ FLPs (n = 1 for line...
Figure 2: Quenching of M═E FLPs by dimerization: (a) generic Mδ+═Eδ− case, and (b) Bergman's arylimido zircon...
Scheme 3: Oxygen-atom extrusion from CO2 by a Ta(V) neopentylidene [27].
Scheme 4: Oxygen-atom transfer from acetone at a Zr(IV) imide [28].
Scheme 5: Alkyne cycloaddition at a Zr(IV) imide [38].
Scheme 6: Nitrile-alkyne cross metathesis at a W(VI) nitride [40,41].
Scheme 7: C–H and H–H addition across a zirconium(IV) imide [42].
Scheme 8: Formal [2 + 2] cycloaddition of methyl isocyanate at a ruthenium silylene [58].
Scheme 9: Oxygen-atom transfer from phenyl isocyanate to a cationic terminal borylene [60].
Scheme 10: Coupling of a phosphorus ylide with an iridium methylene [62].
Scheme 11: Reactions of (PNP)Ir═C(H)Ot-Bu with oxygen-containing heterocumulenes [71].
Scheme 12: Reductive coupling of two CS2 units at (PNP)Ir═C(H)Ot-Bu [73].
Figure 3: Single-crystal X-ray structure of a silver(I) triflate adduct of (PNP)Ir═C(H)Ot-Bu with most H atom...
Scheme 13: Possible routes to C–H functionalization by 1,2-addition across a polarized metal–element multiple ...
Scheme 14: Alkoxycarbene formation by double C–H activation at (PNP)Ir [88].
Scheme 15: Catalytic oxidation of MTBE by multiple C–H activations and nitrene-group transfer to a Mδ−═Eδ+ FLP ...
