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Search for "1,5-enyne" in Full Text gives 4 result(s) in Beilstein Journal of Organic Chemistry.
Transition-metal-catalyzed domino reactions of strained bicyclic alkenes
- Austin Pounder,
- Eric Neufeld,
- Peter Myler and
- William Tam
Beilstein J. Org. Chem. 2023, 19, 487–540, doi:10.3762/bjoc.19.38
- -butyldimethylsilyl-protecting group resulted in the corresponding 1,5-enyne only being produced in a 33% yield. Several different norbornene derivatives were explored and gave the anticipated exo,exo-difunctionalized product in good yield. In contrast, when using an ethylene-bridged bicycloalkene to generate the
Graphical Abstract
Figure 1: Ring-strain energies of homobicyclic and heterobicyclic alkenes in kcal mol−1. a) [2.2.1]-Bicyclic ...
Figure 2: a) Exo and endo face descriptions of bicyclic alkenes. b) Reactivity comparisons for different β-at...
Scheme 1: Ni-catalyzed ring-opening/cyclization cascade of heterobicyclic alkenes 1 with alkyl propiolates 2 ...
Scheme 2: Ni-catalyzed ring-opening/cyclization cascade of heterobicyclic alkenes 8 with β-iodo-(Z)-propenoat...
Scheme 3: Ni-catalyzed two- and three-component difunctionalizations of norbornene derivatives 15 with alkyne...
Scheme 4: Ni-catalyzed intermolecular three-component difunctionalization of oxabicyclic alkenes 1 with alkyn...
Scheme 5: Ni-catalyzed intermolecular three-component carboacylation of norbornene derivatives 15.
Scheme 6: Photoredox/Ni dual-catalyzed coupling of 4-alkyl-1,4-dihydropyridines 31 with heterobicyclic alkene...
Scheme 7: Photoredox/Ni dual-catalyzed coupling of α-amino radicals with heterobicyclic alkenes 30.
Scheme 8: Cu-catalyzed rearrangement/allylic alkylation of 2,3-diazabicyclo[2.2.1]heptenes 47 with Grignard r...
Scheme 9: Cu-catalyzed aminoboration of bicyclic alkenes 1 with bis(pinacolato)diboron (B2pin2) (53) and O-be...
Scheme 10: Cu-catalyzed borylalkynylation of oxabenzonorbornadiene (30b) with B2pin2 (53) and bromoalkynes 62.
Scheme 11: Cu-catalyzed borylacylation of bicyclic alkenes 1.
Scheme 12: Cu-catalyzed diastereoselective 1,2-difunctionalization of oxabenzonorbornadienes 30 for the synthe...
Scheme 13: Fe-catalyzed carbozincation of heterobicyclic alkenes 1 with arylzinc reagents 74.
Scheme 14: Co-catalyzed addition of arylzinc reagents of norbornene derivatives 15.
Scheme 15: Co-catalyzed ring-opening/dehydration of oxabicyclic alkenes 30 via C–H activation of arenes.
Scheme 16: Co-catalyzed [3 + 2] annulation/ring-opening/dehydration domino reaction of oxabicyclic alkenes 1 w...
Scheme 17: Co-catalyzed enantioselective carboamination of bicyclic alkenes 1 via C–H functionalization.
Scheme 18: Ru-catalyzed cyclization of oxabenzonorbornene derivatives with propargylic alcohols for the synthe...
Scheme 19: Ru-catalyzed coupling of oxabenzonorbornene derivatives 30 with propargylic alcohols and ethers 106...
Scheme 20: Ru-catalyzed ring-opening/dehydration of oxabicyclic alkenes via the C–H activation of anilides.
Scheme 21: Ru-catalyzed of azabenzonorbornadiene derivatives with arylamides.
Scheme 22: Rh-catalyzed cyclization of bicyclic alkenes with arylboronate esters 118.
Scheme 23: Rh-catalyzed cyclization of bicyclic alkenes with dienyl- and heteroaromatic boronate esters.
Scheme 24: Rh-catalyzed domino lactonization of doubly bridgehead-substituted oxabicyclic alkenes with seconda...
Scheme 25: Rh-catalyzed domino carboannulation of diazabicyclic alkenes with 2-cyanophenylboronic acid and 2-f...
Scheme 26: Rh-catalyzed synthesis of oxazolidinone scaffolds 147 through a domino ARO/cyclization of oxabicycl...
Scheme 27: Rh-catalyzed oxidative coupling of salicylaldehyde derivatives 151 with diazabicyclic alkenes 130a.
Scheme 28: Rh-catalyzed reaction of O-acetyl ketoximes with bicyclic alkenes for the synthesis of isoquinoline...
Scheme 29: Rh-catalyzed domino coupling reaction of 2-phenylpyridines 165 with oxa- and azabicyclic alkenes 30....
Scheme 30: Rh-catalyzed domino dehydrative naphthylation of oxabenzonorbornadienes 30 with N-sulfonyl 2-aminob...
Scheme 31: Rh-catalyzed domino dehydrative naphthylation of oxabenzonorbornadienes 30 with arylphosphine deriv...
Scheme 32: Rh-catalyzed domino ring-opening coupling reaction of azaspirotricyclic alkenes using arylboronic a...
Scheme 33: Tandem Rh(III)/Sc(III)-catalyzed domino reaction of oxabenzonorbornadienes 30 with alkynols 184 dir...
Scheme 34: Rh-catalyzed asymmetric domino cyclization and addition reaction of 1,6-enynes 194 and oxa/azabenzo...
Scheme 35: Rh/Zn-catalyzed domino ARO/cyclization of oxabenzonorbornadienes 30 with phosphorus ylides 201.
Scheme 36: Rh-catalyzed domino ring opening/lactonization of oxabenzonorbornadienes 30 with 2-nitrobenzenesulf...
Scheme 37: Rh-catalyzed domino C–C/C–N bond formation of azabenzonorbornadienes 30 with aryl-2H-indazoles 210.
Scheme 38: Rh/Pd-catalyzed domino synthesis of indole derivatives with 2-(phenylethynyl)anilines 212 and oxabe...
Scheme 39: Rh-catalyzed domino carborhodation of heterobicyclic alkenes 30 with B2pin2 (53).
Scheme 40: Rh-catalyzed three-component 1,2-carboamidation reaction of bicyclic alkenes 30 with aromatic and h...
Scheme 41: Pd-catalyzed diarylation and dialkenylation reactions of norbornene derivatives.
Scheme 42: Three-component Pd-catalyzed arylalkynylation reactions of bicyclic alkenes.
Scheme 43: Three-component Pd-catalyzed arylalkynylation reactions of norbornene and DFT mechanistic study.
Scheme 44: Pd-catalyzed three-component coupling N-tosylhydrazones 236, aryl halides 66, and norbornene (15a).
Scheme 45: Pd-catalyzed arylboration and allylboration of bicyclic alkenes.
Scheme 46: Pd-catalyzed, three-component annulation of aryl iodides 66, alkenyl bromides 241, and bicyclic alk...
Scheme 47: Pd-catalyzed double insertion/annulation reaction for synthesizing tetrasubstituted olefins.
Scheme 48: Pd-catalyzed aminocyclopropanation of bicyclic alkenes 1 with 5-iodopent-4-enylamine derivatives 249...
Scheme 49: Pd-catalyzed, three-component coupling of alkynyl bromides 62 and norbornene derivatives 15 with el...
Scheme 50: Pd-catalyzed intramolecular cyclization/ring-opening reaction of heterobicyclic alkenes 30 with 2-i...
Scheme 51: Pd-catalyzed dimer- and trimerization of oxabenzonorbornadiene derivatives 30 with anhydrides 268.
Scheme 52: Pd-catalyzed Catellani-type annulation and retro-Diels–Alder of norbornadiene 15b yielding fused xa...
Scheme 53: Pd-catalyzed hydroarylation and heteroannulation of urea-derived bicyclic alkenes 158 and aryl iodi...
Scheme 54: Access to fused 8-membered sulfoximine heterocycles 284/285 via Pd-catalyzed Catellani annulation c...
Scheme 55: Pd-catalyzed 2,2-bifunctionalization of bicyclic alkenes 1 generating spirobicyclic xanthone deriva...
Scheme 56: Pd-catalyzed Catellani-type annulation and retro-Diels–Alder of norbornadiene (15b) producing subst...
Scheme 57: Pd-catalyzed [2 + 2 + 1] annulation furnishing bicyclic-fused indanes 281 and 283.
Scheme 58: Pd-catalyzed ring-opening/ring-closing cascade of diazabicyclic alkenes 130a.
Scheme 59: Pd-NHC-catalyzed cyclopentannulation of diazabicyclic alkenes 130a.
Scheme 60: Pd-catalyzed annulation cascade generating diazabicyclic-fused indanones 292 and indanols 294.
Scheme 61: Pd-catalyzed skeletal rearrangement of spirotricyclic alkenes 176 towards large polycyclic benzofur...
Scheme 62: Pd-catalyzed oxidative annulation of aromatic enamides 298 and diazabicyclic alkenes 130a.
Scheme 63: Accessing 3,4,5-trisubstituted cyclopentenes 300, 301, 302 via the Pd-catalyzed domino reaction of ...
Scheme 64: Palladacycle-catalyzed ring-expansion/cyclization domino reactions of terminal alkynes and bicyclic...
Scheme 65: Pd-catalyzed carboesterification of norbornene (15a) with alkynes, furnishing α-methylene γ-lactone...
Formal total synthesis of macarpine via a Au(I)-catalyzed 6-endo-dig cycloisomerization strategy
- Jiayue Fu,
- Bingbing Li,
- Zefang Zhou,
- Maosheng Cheng,
- Lu Yang and
- Yongxiang Liu
Beilstein J. Org. Chem. 2022, 18, 1589–1595, doi:10.3762/bjoc.18.169
- . The convergent synthetic strategies feature the utilization of Au(I)-catalyzed cycloisomerizations of a 1,5-enyne and alkynyl ketone substrates, which were prepared by Sonogashira coupling reactions. Keywords: benzo[c]phenanthridine alkaloids; 1,5-enyne; formal total synthesis; gold catalysis
- ) and tert-butyldimethylsilyl chloride (TBSCl) (Scheme 5). To find the best cycloisomerization conditions, the 1,5-enyne substrate 10 was subjected to different reaction conditions as listed in Table 1. It was observed that [1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene]gold(I) chloride (IPrAuCl
Graphical Abstract
Scheme 1: Classification of benzo[c]phenanthridine alkaloids.
Scheme 2: Representative synthetic strategies for macarpine (1).
Scheme 3: Retrosynthetic analysis of marcarpine precursor 12 for a partial synthesis.
Scheme 4: Syntheses of precursors 5 and 8.
Scheme 5: Synthesis of enol silyl ether 10.
Scheme 6: Formal total synthesis of macarpine (1).
Gold-catalyzed propargylic substitutions: Scope and synthetic developments
- Olivier Debleds,
- Eric Gayon,
- Emmanuel Vrancken and
- Jean-Marc Campagne
Beilstein J. Org. Chem. 2011, 7, 866–877, doi:10.3762/bjoc.7.99
- been described by Fairlamb [82]. We were also able, from compound 2, to develop a 1,5-enyne metathesis that leads to functionalized cyclobutenes 38 (Scheme 20) [83], which was subsequently nicely illustrated by Goess in a total synthesis of grandisol [84]. From isoxazolines 23, we were also able to
Graphical Abstract
Scheme 1: Gold-catalyzed propargylic substitutions.
Scheme 2: Propargylic substitution: scope of substrates.
Scheme 3: Propargylic substitutions on allylic/propargylic substrates.
Scheme 4: Direct propargylic substitutions: Scope of nucleophiles.
Scheme 5: Meyer–Schuster rearrangements.
Scheme 6: Silyl-protected propargyl alcohols in propargylic substitutions.
Scheme 7: Acetylacetone as nucleophile in direct propargylic substitution.
Scheme 8: Enantiomerically enriched propargylic alcohols.
Scheme 9: Scope of ‘activated’ alcohols in direct substitution reactions.
Scheme 10: BF3 vs AuCl3 in propargylic substitutions [25].
Scheme 11: The use of bis-nucleophiles in direct propargylic substitutions.
Scheme 12: Tandem reactions from protected hydroxylamines and propargylic alcohols. P = Cbz, PhSO2.
Scheme 13: Tentative hydrolysis of bis-adduct 24a.
Scheme 14: Iron-catalyzed propargylic substitutions.
Scheme 15: Isoxazolines formation.
Scheme 16: Addition of nucleophiles to isoxazolines.
Scheme 17: Potential mechanistic pathways.
Scheme 18: Synthesis of furans from homoproargylic alcohols.
Scheme 19: Synthesis of furans.
Scheme 20: Propargylic substitutions: Synthetic applications. GH2 = Grubbs–Hoveyda 2nd generation catalyst.
When gold can do what iodine cannot do: A critical comparison
- Sara Hummel and
- Stefan F. Kirsch
Beilstein J. Org. Chem. 2011, 7, 847–859, doi:10.3762/bjoc.7.97
- ) activated by AgSbF6 (Scheme 7) [91]. A 1,5-enyne disubstituted at the terminal carbon of the alkene (e.g., 19) leads to a very selective 5-endo carbocyclization where no side products resulting from 5-exo or 6-endo modes were observed. A mechanism was proposed involving a cationic intermediate after
- migration of R3 are strictly limited to compounds that bear a quaternary center (R3 = alkyl, R2 ≠ H). As shown for the gold(I)-catalyzed reaction of 1,5-enyne 53, the formation of the bicyclo[3.1.0]hexene 54 is driven by the release of ring strain. Enynes with R3 = H undergo exclusively a hydride shift to
Graphical Abstract
Scheme 1: Mechanistic scenarios for alkyne activation.
Scheme 2: Synthesis of 3(2H)-furanones.
Scheme 3: Synthesis of furans.
Scheme 4: Formation of dihydrooxazoles.
Scheme 5: Variation on indole formation.
Scheme 6: Formation of naphthalenes.
Scheme 7: Formation of indenes.
Scheme 8: Iodocyclization of 3-silyloxy-1,5-enynes.
Scheme 9: 5-Endo cyclizations with concomitant nucleophilic trapping.
Scheme 10: Reactivity of 3-BocO-1,5-enynes.
Scheme 11: Intramolecular nucleophilic trapping.
Scheme 12: Approach to azaanthraquinones.
Scheme 13: Carbocyclizations with enol derivatives.
Scheme 14: Gold-catalyzed cyclization modes for 1,5-enynes.
Scheme 15: Iodine-induced cyclization of 1,5-enynes.
Scheme 16: Diverse reactivity of 1,6-enynes.
Scheme 17: Iodocyclization of 1,6-enynes.
Scheme 18: Cyclopropanation of alkenes with 1,6-enynes.
Scheme 19: Cyclopropanation of alkenes with 1,6-enynes.
