In contrast to the production of simple bulk chemicals and polymers, which started shortly after the discovery of the “olefin scrambling” reaction, it was not until much later that this transformation was “rediscovered” by the academic world. In the last decade of the 20thcentury, the so-called olefin metathesis reaction gained real significance in advanced organic synthesis. The development of well-defined catalysts and an understanding of the reaction mechanism prompted an extraordinary scientific turnaround, revolutionizing retro-synthetic planning in total synthesis groups and in medicinal chemistry laboratories around the world. The importance of “the development of the metathesis method in organic synthesis” has been fully recognized by the award of the Nobel Prize in Chemistry for 2005.
See also the Thematic Series:
Progress in metathesis chemistry II
Graphical Abstract
Figure 1: General layout for modifications of ruthenium-based olefin metathesis catalysts (red: anionic ligan...
Scheme 1: Synthesis of 1, 2 and 3.
Figure 2: Details of the 1H NMR spectra acquired during the synthesis of 2 and the FD-MS spectrum of 2 isolat...
Figure 3: ORTEP drawing of 3. Thermal ellipsoids are drawn at 50% probability level. Hydrogen atoms are omitt...
Figure 4: Polymerisation of 4 as a function of time, initiated by 1, 2 or 3, monitored by 1H NMR spectroscopy...
Figure 5: Polymerisations of 6 as a function of time, initiated by 1–3, monitored by 1H NMR spectroscopy (sol...
Figure 6: The RCM reaction of 7 as a function of time, catalysed by 1, 2 or 3, monitored by 1H NMR spectrosco...
Graphical Abstract
Figure 1: Starting allylcarboranes 1a–1c and O-allylcyclodextrins 2a–2c.
Scheme 1: Cross-metathesis of allylcarboranes 1 and O-allylcyclodextrins 2.
Graphical Abstract
Scheme 1: Light activated metathesis of trans-2-pentene.
Scheme 2: Light induced generation of metathesis active species 2.
Figure 1: Well-defined tungsten photoactive catalysts.
Figure 2: The first ruthenium based complexes for PROMP.
Figure 3: Cyclic strained alkenes for PROMP.
Scheme 3: Proposed mechanism for photoactivation of sandwich complexes.
Figure 4: Ruthenium and osmium complexes with p-cymene and phosphane ligands for PROMP.
Figure 5: Commercially available photoactive ruthenium precatalyst.
Figure 6: Some of the rings produced by photo-RCM.
Scheme 4: Photopromoted ene-yne RCM by cationic allenylidene ruthenium complex 14.
Figure 7: Dihydrofurans synthesised by photopromoted ene-yne RCM.
Figure 8: Ruthenium complexes with p-cymene and NHC ligands.
Scheme 5: Ruthenium NHC complexes for PROMP containing p-cymene and trifluroacetate (17, 19) or phenylisonitr...
Figure 9: Photoactivated cationic ROMP precatalysts.
Figure 10: Different monomers for PROMP.
Scheme 6: Proposed mechanism for photoinitiated polymerisation by 22 and 23.
Figure 11: Light-induced cationic catalysts for ROMP.
Figure 12: Sulfur chelated ruthenium benzylidene pre-catalysts for olefin metathesis.
Scheme 7: Proposed mechanism for the photoactivation of sulfur-chelated ruthenium benzylidene.
Figure 13: Photoacid generators for photoinduced metathesis.
Scheme 8: Synthesis of precatalysts 36 and 37.
Scheme 9: Trapping of proposed intermediate 41.
Figure 14: Encapsulated 39, isolated from the monomer.
Graphical Abstract
Figure 1: Representative olefin metathesis catalysts.
Figure 2: Highly active olefin metathesis catalysts bearing NHC with backbone substitution.
Scheme 1: Synthesis of the free NHCs.
Scheme 2: Synthesis of [RhCl(CO)2(NHC)] complexes.
Scheme 3: Synthesis of [RuCl2(NHC)(PCy3)(Ind)] complexes.
Graphical Abstract
Figure 1: Olefin isomerization during ADMET polymerization.
Figure 2: Ru–indenylidene metathesis catalysts C1 and C2, “boomerang” complexes C3, and Hoveyda–Grubbs 2nd ge...
Figure 3: Representative scheme for the in situ generated Ru–indenylidene [38].
Figure 4: Synthesis of the studied α,ω-diene, its ADMET polymerization, and the strategy to evaluate isomeriz...
Figure 5: GPC traces of the polymerizations performed at 60, 80, 100 and 120 ºC in presence of a) 0.5 mol % C1...
Figure 6: GC-MS study of the acid-catalyzed degradation products of polymers P19, P20, P21, and P22.
Figure 7: GPC traces of polymerizations performed with C1 at 80, 100, and 120 ºC. Samples taken at 5 min (―–)...
Figure 8: DSC traces of ADMET polymers P11 and P12 (Table 1, entries 11 and 12, respectively).
Graphical Abstract
Figure 1: Ruthenium precatalysts for olefin metathesis.
Figure 2: Structure of precatalyst 3 and 4.
Scheme 1: Synthesis of catalysts 4a–g.
Figure 3: Kinetic studies of RCM of 8 (0.1 M) with precatalysts 4a–g (1 mol %) in CD2Cl2 at 30 °C.
Graphical Abstract
Scheme 1: Reaction of homobimetallic ruthenium–indenylidene complex 1 with ethylene.
Scheme 2: Schematic illustration of tandem assisted catalysis with complexes 1 and 2.
Scheme 3: Tandem RCM/ATRC of 2,2,2-trichloro-N-(octa-1,7-dien-3-yl)acetamide (4) catalyzed by complex 1.
Scheme 4: Ruthenium catalyzed transformation of substrate 16.
Graphical Abstract
Figure 1: Ru-based metathesis catalysts.
Scheme 1: RCM of an allyl ether catalyzed by catalyst H.
Figure 2: Solvent screening for the RCM of 1 catalyzed by H (standardized conditions as denoted in Scheme 1).
Figure 3: Comparison of catalysts D, E and H in toluene and acetic acid (standardized conditions as denoted i...
Figure 4: Conversion vs catalyst loading for the RCM of 1 in acetic acid (standardized conditions as denoted ...
Scheme 2: Catalyst screening for RCM of acrylate 3a.
Figure 5: Acrylates 3 and their RCM products 4.
Scheme 3: Ring closing enyne metathesis reactions.
Scheme 4: Cross metathesis reactions with allylic alcohol 8.
Graphical Abstract
Figure 1: Nanoscale HAp: calcium phosphate hydroxide (Ca5(PO4)3OH) as evidenced by XRD measurements (a), SEM ...
Scheme 1: ROMP-based synthesis of cis-5-cyclooctene-trans-1,2-diol based polymeric monolithic scaffolds.
Figure 2: (a) Cell growth of human adipose tissue-derived stromal cells. Each data point is the average of 12...
Graphical Abstract
Scheme 1: a) Variation of olefin metathesis: CM = cross-metathesis; RCM = ring-closing metathesis; ROM = ring...
Figure 1: Allylic hydroxy activation in RCM [19].
Figure 2: Possible complexes generated through preassociation of allylic alcohol with ruthenium.
Scheme 2: The influence of different OR groups on ring size-selectivity [21].
Scheme 3: Synthesis of palmerolide A precursors by Nicolaou et al. illustrates enhancement by an allylic hydr...
Scheme 4: a) Acceleration of ring-closing enyne metathesis by the allylic hydroxy group [23]. b) Proposed mode of...
Scheme 5: a) Effect of the hydroxy group on the rate and steroselectivity of ROCM [24]. b) Proposed H-bonded ruth...
Scheme 6: Plausible explanation for chemoselective CM of diene 16 [25].
Scheme 7: a) Efficient cross-metathesis of S-allylcysteine [17]. b) Comparison of relative reactivity between all...
Scheme 8: a) Macrocycle synthesis by carbonyl-relayed RCM. b) Putative complex in carbonyl-relayed RCM [33].
Scheme 9: a) Sulfur assisted cross-metathesis [17]. b) Putative unproductive chelates for larger ring sizes gener...
Scheme 10: Functionalization of Mukaiyama aldol product by CM in aqueous media [37].
Scheme 11: Comparison of reactivity between allyl sulfides and allyl selenides in aqueous cross-metathesis [38].
Scheme 12: Ring-closing metathesis on a protein [18].
Scheme 13: Expanded substrate scope of cross-metathesis on proteins [38].
Graphical Abstract
Scheme 1: Alkene metathesis mechanism.
Scheme 2: Metathesis possibilities.
Scheme 3: Metathesis with Re-based alumina supported catalysts.
Figure 1: (E/Z) ratio as a function of conversion. a) MeReO3 supported on alumina and b) MeReO3 supported on ...
Scheme 4: Alkene selectivity of metathesis reactions.
Scheme 5: Hybrid organic–inorganic catalyst containing a Ru–NHC unit.
Graphical Abstract
Figure 1: Grubbs 1 and Hoveyda–Grubbs 2 catalysts.
Figure 2: Zhan catalyst-1B.
Scheme 1: Metathesis reactions studied.
Figure 3: Conversion curves for the RCM of DEDAM with 3 in CH2Cl2 (open squares), 3/SBA-15 in CH2Cl2 (inverte...
Figure 4: Filtration experiments with 3/SBA-15. RCM of DEDAM in benzene (circles), 1,7-octadiene in cyclohexa...
Figure 5: Metathesis of methyl oleate (open symbols) and methyl 10-undecenoate (filled symbols) with 3/MCM-41...
Figure 6: UV–vis spectra of 3/SBA-15 (curve 2) and of 3 (curve 1) in dichloromethane (c = 0.001 mol/L, l = 0....
Figure 7: Spectra of the Ru 3d–C 1s photoelectrons for neat compound 3 (1), catalyst sample 3/SBA-15 (2) and ...
Graphical Abstract
Scheme 1: Alkyne metathesis based on the Katz mechanism.
Scheme 2: Reaction patterns of alkyne metathesis.
Scheme 3: Typical examples from traditional catalyst systems.
Scheme 4: Ligand synthesis and catalyst design.
Scheme 5: Catalysts synthesis using high- and low-oxidation-state routes (for 6a, X = Li or K; for 6b, X = K)....
Figure 1: Alkylidyne complexes 9 and 10.
Scheme 6: Design strategy of Fürstner’s new system.
Scheme 7: Synthetic routes of Fürstner’s new catalysts.
Scheme 8: Lewis acid addition of 26 and 28.
Scheme 9: Preparation of the silanolate–alkylidyne tungsten complex 39.
Graphical Abstract
Scheme 1: Strategy for the ROMP of norbornene by Ru-benzylidene dendrimers to form dendrimer-cored stars.
Scheme 2: Third-generation (16 Ru atoms) ruthenium-benzylidene dendrimer that catalyzes the ROMP of norbornen...
Scheme 3: Multiple carbon–carbon bond formation upon RCM and CM, and the complete switch of selectivity in th...
Scheme 4: Example of chemo-, regio- and stereoselective CM of polyolefin dendrimers catalyzed by the 2nd gene...
Scheme 5: Example of chemo-, regio- and stereoselective CM of polyolefin dendrimers catalyzed by the 2nd gene...
Scheme 6: Dendrimer construction scheme from a 9-olefinic dendrimer to a 27-olefinic dendrimer by regio-and s...
Scheme 7: Synthesis of the water-soluble dendritic nanoreactor 7 for olefin metathesis in water without co-so...
Graphical Abstract
Scheme 1: Synthesis of complex 1a.
Scheme 2: Synthesis of complexes 2 and 3.
Scheme 3: Synthesis of complexes 1b–i.
Figure 1: Naphthyl-group region of 1H,1H-COSY NMR for 1g in CD2Cl2 at −80 °C.
Figure 2: 1H NMR (top) and NOE difference spectrum (bottom) of 1g in CD2Cl2 at −80 °C, saturating the methyli...
Scheme 4: Conformational isomerism in complex 1g.
Figure 3: Olefin and alkylidene-proton region of the 1H NMR (top) and NOE difference spectrum (bottom) of 1e ...
Scheme 5: Conformational isomerism in complex 1e.
Figure 4: Olefin and alkyl group region of the 1H NMR (top) and NOE difference spectrum (bottom) of 1e in CD2...
Graphical Abstract
Scheme 1: Interaction of triple bonds with a metal carbene.
Scheme 2: General scheme for EYCM and side reactions.
Figure 1: Selected ruthenium catalysts able to perform EYCM.
Scheme 3: Catalytic cycle with initial interaction of a metal methylidene with the triple bond.
Scheme 4: Catalytic cycle with initial interaction of a metal alkylidene with the triple bond.
Scheme 5: Formation of 2,3-disubstituted dienes via cross-metathesis of alkynes with ethylene.
Figure 2: Applications of EYCM with ethylene in natural product synthesis.
Scheme 6: Application of EYCM in sugar chemistry.
Scheme 7: EYCM as determining step to form vinylcyclopropane derivatives.
Scheme 8: Sequential EYCM with ethylene/nucleophilic substitution or elimination.
Scheme 9: Various regioselectivities in EYCM of silylated alkynes.
Scheme 10: High regio- and stereoselectivities obtained for EYCM with styrenes.
Scheme 11: EYCM of terminal olefins with internal borylated alkynes.
Scheme 12: Synthesis of propenylidene cyclobutane via EYCM.
Scheme 13: Efficient EYCM with vinyl ethers.
Scheme 14: From cyclopentene to cyclohepta-1,3-dienes via cyclic olefin-alkyne cross-metathesis.
Scheme 15: Ring expansion via EYCM from bicyclic olefins.
Scheme 16: Ring contraction resulting from EYCM of cyclooctadiene.
Scheme 17: Preparation of bicyclic products via diene-alkyne cross-metathesis.
Scheme 18: Ethylene helping effect in EYCM.
Scheme 19: Stereoselective EYCM in the presence of ethylene.
Scheme 20: Sequential ethenolysis/EYCM applied to unsaturated fatty acid esters.
Scheme 21: Sequential ethenolysis/EYCM applied to symmetrical unsaturated fatty acid derivatives for the produ...
Graphical Abstract
Scheme 1: Well-defined Mo- and Ru-alkylidene metathesis catalysts.
Scheme 2: Representative pyrrolidine-based iminocyclitols.
Scheme 3: Synthesis of (±)-(2R*,3R*,4S*)-2-hydroxymethylpyrrolidin-3,4-diol (18), (±)-2-hydroxymethylpyrrolid...
Scheme 4: Synthesis of enantiopure iminocyclitol (−)-(2S,3R,4S,5S)-2,5-dihydroxymethylpyrrolidin-3,4-diol (23...
Scheme 5: Synthesis of 1,4-dideoxy-1,4-imino-D-allitol (29) and formal synthesis of (2S,3R,4S)-3,4-dihydroxyp...
Scheme 6: Synthesis of iminocyclitols 35 and 36.
Scheme 7: Total synthesis of iminocyclitols 40 and 44.
Scheme 8: Synthesis of 2,5-dideoxy-2,5-imino-D-mannitol [(+)-DMDP] (49) and (−)-bulgecinine (50).
Scheme 9: Synthesis of (+)-broussonetine G (53).
Scheme 10: Structural features of broussonetines 54.
Scheme 11: Synthesis of broussonetines by cross-metathesis.
Scheme 12: Representative piperidine-based iminocyclitols.
Scheme 13: Total synthesis of 1-deoxynojirimycin (62) and 1-deoxyaltronojirimycin (65).
Scheme 14: Synthesis by RCM of 1-deoxymannonojirimycin (63) and 1-deoxyallonojirimycin (66).
Scheme 15: Total synthesis of (+)-1-deoxynojirimycin (62).
Scheme 16: Synthesis of ent-1,6-dideoxynojirimycin (83) and 5-amino-1,5,6-trideoxyaltrose (84).
Scheme 17: Synthesis of 1-deoxygalactonojirimycin (64), 1-deoxygulonojirimycin (91) and 1-deoxyidonojirimycin (...
Scheme 18: Synthesis of L-1-deoxyaltronojirimycin (96).
Scheme 19: Synthesis of 1-deoxymannonojirimycin (63) and 1-deoxyaltronojirimycin (65).
Scheme 20: Synthesis of 5-des(hydroxymethyl)-1-deoxymannonojirimycin (111) and 5-des(hydroxymethyl)-1-deoxynoj...
Scheme 21: Synthesis of D-1-deoxygulonojirimycin (91) and L-1-deoxyallonojirimycin (122).
Scheme 22: Total synthesis of fagomine (129), 3-epi-fagomine (126) and 3,4-di-epi-fagomine (130).
Scheme 23: Total synthesis of (+)-adenophorine (135).
Scheme 24: Total synthesis of (+)-5-deoxyadenophorine (138) and analogues 142–145.
Scheme 25: Synthesis by RCM of 1,6-dideoxy-1,6-iminoheptitols 148 and 149.
Scheme 26: Synthesis by RCM of oxazolidinyl azacycles 152 and 154.
Scheme 27: Representative azepane-based iminocyclitols.
Scheme 28: Synthesis of hydroxymethyl-1-(4-methylphenylsulfonyl)azepane 3,4,5-triol (169).
Scheme 29: Synthesis by RCM of tetrahydropyridin-3-ol 171 and tetrahydroazepin-3-ol 173.