- Quantifying Error Correction through a Rule-Based Model of Strand Escape from an [ n]-Rung Ladder
-
The rational design of 3D structures (MOFs, COFs, etc.) is presently limited by our understanding of how the molecular constituents assemble. The common approach of using reversible interactions (covalent or noncovalent) becomes challenging, especially when the target is made from multivalent building blocks and/or under conditions of slow exchange, as kinetic traps and nonequilibrium product distributions are possible. Modeling the time course of the assembly process is difficult because the reaction networks include many possible pathways and intermediates. Here we show that rule-based kinetic simulations efficiently model dynamic reactions involving multivalent building blocks. We studied "strand escape from an [n]-rung ladder" as an example of a dynamic process characterized by a complex reaction network. The strand escape problem is important in that it predicts the time a dynamic system needs to backtrack from errors involving [n]-misconnections. We quantify the time needed for error correction as a function of the dissociation rate coefficient, strand valency, and seed species. We discuss the simulation results in relation to a simple probabilistic framework that captures the power law dependence on the strand's valency, and the inverse relationship to the rung-opening rate coefficient. The model also tests the synthetic utility of a one-rung (i.e., hairpin) seed species, which, at intermediate times, bifurcates to a long-lived, fully formed [n]-rung ladder and a pair of separated strands. Rule-based models thus give guidance to the planning of a dynamic covalent synthesis by predicting time to maximum yield of persistent intermediates for a particular set of rate coefficients and valency.
- Cencer, Morgan M.,Greenlee, Andrew J.,Moore, Jeffrey S.
-
supporting information
p. 162 - 168
(2020/01/03)
-
- Robust Alkyne Metathesis Catalyzed by Air Stable d2Re(V) Alkylidyne Complexes
-
We report in this communication the first example of catalytic alkyne metathesis reactions mediated by well-defined non-d0 alkylidyne complexes. The air-stable d2 Re(V) alkylidyne complex Re4, bearing two PO-chelating ligands and a labile pyridine ligand, could catalyze homometathesis of internal alkynes with a broad substrate scope, including alcohols, amines, and even carboxylic acids. The catalyst can tolerate heating, air, and moisture in both solid and solution states, and the catalytic metathesis reactions could proceed normally in wet solvents.
- Cui, Mingxu,Bai, Wei,Sung, Herman H. Y.,Williams, Ian D.,Jia, Guochen
-
supporting information
p. 13339 - 13344
(2020/09/03)
-
- One-Pot Domino Synthesis of Diarylalkynes/1,4-Diaryl-1,3-diynes by [9,9-Dimethyl-4,5-bis(diphenylphosphino)xanthene] (Xantphos)–Copper(I) Iodide–Palladium(II) Acetate-Catalyzed Double Sonogashira-Type Reaction
-
The low loading combination of the complex [9,9-dimethyl-4,5-bis(diphenylphosphino)xanthene] (Xantphos)copper(I) iodide and simple ligand-free palladium(II) acetate was found to be efficient for the domino synthesis of diarylalkynes by the reaction of aryl halides with trimethylsilylethynylene or bis(trimethylsilyl)acetylene in a single-step procedure. The unsymmetrical diarylalkynes can be obtained through a one-pot two-step approach. The reactions of aryl bromides with 1,4-bis(trimethylsilyl)butadiyne also furnished the corresponding 1,4-diaryl-1,3-diynes in a similar fashion. This route to diarylalkynes and 1,4-diaryl-1,3-diynes is complementary to previously reported synthetic procedures. (Figure presented.).
- Qiu, Shaozhong,Zhang, Caiyang,Qiu, Rui,Yin, Guodong,Huang, Jinkun
-
p. 313 - 321
(2018/01/15)
-
- The [2 + 2] Cycloaddition-Retroelectrocyclization and [4 + 2] Hetero-Diels-Alder Reactions of 2-(Dicyanomethylene)indan-1,3-dione with Electron-Rich Alkynes: Influence of Lewis Acids on Reactivity
-
The reaction of electrophilic 2-(dicyanomethylene)indan-1,3-dione (DCID) with substituted, electron-rich alkynes provides two classes of push-pull chromophores with interesting optoelectronic properties. The formal [2 + 2] cycloaddition-retroelectrocycliz
- Donckele, Etienne J.,Finke, Aaron D.,Ruhlmann, Laurent,Boudon, Corinne,Trapp, Nils,Diederich, Fran?ois
-
supporting information
p. 3506 - 3509
(2015/07/28)
-
- Tetraarylcyclobutadienecyclopentadienylcobalt complexes: Synthesis, electronic spectra, magnetic circular dichroism, linear dichroism, and TD DFT calculations
-
The known (tetraphenyl-η4-cyclobutadiene)- η5-cyclopentadienylcobalt (1) and a series of its new substituted derivatives have been prepared. The electronic states of a few representatives have been characterized by absorption and magnetic circular dichroism. Time-dependent density functional theory has been used to arrive at spectral assignments for several prominent low-energy bands. The absorption spectra of the radical ions of 1 have also been recorded.
- Kottas, Gregg S.,Brotin, Thierry,Schwab, Peter F. H.,Gala, Kamal,Havlas, Zdenek,Kirby, James P.,Miller, John R.,Michl, Josef
-
p. 3251 - 3264
(2014/08/05)
-
- 6,6-Dicyanopentafulvenes: Electronic structure and regioselectivity in [2 + 2] cycloaddition-retroelectrocyclization reactions
-
We present an investigation of the electronic properties and reactivity behavior of electron-accepting 6,6-dicyanopentafulvenes (DCFs). The electron paramagnetic resonance (EPR) spectra of the radical anion of a tetrakis(silylalkynyl) DCF, generated by Na
- Finke, Aaron D.,Dumele, Oliver,Zalibera, Michal,Confortin, Daria,Cias, Pawel,Jayamurugan, Govindasamy,Gisselbrecht, Jean-Paul,Boudon, Corinne,Schweizer, W. Bernd,Gescheidt, Georg,Diederich, Francois
-
supporting information
p. 18139 - 18146
(2013/01/15)
-
- A novel palladium-catalyzed cross-coupling of thiomethylated alkynes with functionalized organozinc reagents
-
A range of methylthio-substituted acetylenes undergo smooth palladium-catalyzed cross-coupling reactions with functionalized aryl-, heteroaryl-, and alkylzinc reagents using the Pd(OAc)2/DPE-Phos catalytic system at 25 or 50 C without the need for copper salts. Georg Thieme Verlag Stuttgart.
- Melzig, Laurin,Stemper, Jeremy,Knochel, Paul
-
experimental part
p. 2085 - 2091
(2010/08/19)
-
- Synthetic, mechanistic, and computational investigations of nitrile-alkyne cross-metathesis
-
The terminal nitride complexes NW(OC(CF3)2Me) 3(DME) (1-DME), [Li(DME)2][NW(OC(CF3) 2Me)4] (2), and [NW(OCMe2CF3) 3]3 (3) were prepared in good yield by salt elimination from [NWCl3]4. X-ray structures revealed that 1-DME and 2 are monomeric in the solid state. All three complexes catalyze the cross-metathesis of 3-hexyne with assorted nitriles to form propionitrile and the corresponding alkyne. Propylidyne and substituted benzylidyne complexes RCW(OC(CF3)2Me)3 were isolated in good yield upon reaction of 1-DME with 3-hexyne or 1-aryl-1-butyne. The corresponding reactions failed for 3. Instead, EtCW(OC(CF3)Me2) 3 (6) was prepared via the reaction of W2(OC(CF 3)Me2)6 with 3-hexyne at 95°C. Benzylidyne complexes of the form ArCW(OC(CF3)Me2)3 (Ar = aryl) then were prepared by treatment of 6 with the appropriate symmetrical alkyne ArCCAr. Three coupled cycles for the interconversion of 1-DME with the corresponding propylidyne and benzylidyne complexes via [2 + 2] cycloaddition-cycloreversion were examined for reversibility. Stoichiometric reactions revealed that both nitrile-alkyne cross-metathesis (NACM) cycles as well as the alkyne cross-metathesis (ACM) cycle operated reversibly in this system. With catalyst 3, depending on the aryl group used, at least one step in one of the NACM cycles was irreversible. In general, catalyst 1-DME afforded more rapid reaction than did 3 under comparable conditions. However, 3 displayed a slightly improved tolerance of polar functional groups than did 1-DME. For both 1-DME and 3, ACM is more rapid than NACM under typical conditions. Alkyne polymerization (AP) is a competing reaction with both 1-DME and 3. It can be suppressed but not entirely eliminated via manipulation of the catalyst concentration. As AP selectively removes 3-hexyne from the system, tandem NACM-ACM-AP can be used to prepare symmetrically substituted alkynes with good selectivity, including an arylene-ethynylene macrocycle. Alternatively, unsymmetrical alkynes of the form EtCCR (R variable) can be prepared with good selectivity via the reaction of RCN with excess 3-hexyne under conditions that suppress AP. DFT calculations support a [2 + 2] cycloaddition-cycloreversion mechanism analogous to that of alkyne metathesis. The barrier to azametalacyclobutadiene ring formation/breakup is greater than that for the corresponding metalacyclobutadiene. Two distinct high-energy azametalacyclobutadiene intermediates were found. These adopted a distorted square pyramidal geometry with significant bond localization.
- Geyer, Andrea M.,Wiedner, Eric S.,Gary, J. Brannon,Gdula, Robyn L.,Kuhlmann, Nicola C.,Johnson, Marc J. A.,Dunietz, Barry D.,Kampf, Jeff W.
-
scheme or table
p. 8984 - 8999
(2009/02/03)
-
- The use of calcium carbide in one-pot synthesis of symmetric diaryl ethynes
-
An efficient Pd-catalyzed copper and amine free coupling reaction of acetylene and aryl bromides was achieved with calcium carbide as an acetylene source, using inorganic base and easily prepared, air-stable aminophosphine ligand in common organic solvents, providing symmetric diaryl ethynes in one-pot with yields ranged from moderate to excellent. The Royal Society of Chemistry 2006.
- Zhang, Weiwei,Wu, Huayue,Liu, Zhiqing,Zhong, Ping,Zhang, Lin,Huang, Xiaobo,Cheng, Jiang
-
p. 4826 - 4828
(2007/10/03)
-
- Synthesis and non-linear optical properties of new ionic species: Tolan and diphenylbutadiyne with trimethylammonio and dimethylamino groups
-
As new ionic organic species for second-order non-linear optical (NLO) materials, 4-{[4-(dimethylamino)phenyl]ethynyl)phenyltrimethylarnmonium iodide (1a), 4-{[4-(dimethylamino)phenyl]butadiynyl}phenyltri-methylammoniura iodide (2a) and their derivatives
- Umezawa, Hirohito,Okada, Shuji,Oikawa, Hidetoshi,Matsuda, Hiro,Nakanishi, Hachiro
-
p. 468 - 472
(2007/10/03)
-
- Highly Active Trialkoxymolybdenum(VI) Alkylidyne Catalysts Synthesized by A Reductive Recycle Strategy
-
A systematic study of alkyne metathesis catalyzed by trialkoxymolybdenum(VI) alkylidyne complexes is reported, in which substrate functional groups, alkynyl substituents, and catalyst ligands are varied. Sterically hindered trisamidomolybdenum(VI) propylidyne complex 5 was prepared conveniently through a previously communicated reductive recycle strategy. Alcoholysis of 5 with various phenols/alcohols provides a set of active catalysts for alkyne metathesis at room temperature, among which the catalyst with p-nitrophenol as ligand shows the highest catalytic activity and is compatible with a variety of functional groups and solvents. A key finding that enabled the use of highly active molybdenum(VI) catalysts is replacement of the commonly used propynyl substituents on the starting alkyne substrates with butynyl groups. Under reduced pressure using 1,2,4-trichlorobenzene as an involatile solvent, the alkyne metathesis of butynyl substituted compounds proceeds well at 30 °C providing high yields (83%-97%) of dimers. Rationalization of the special role played by butynyl substrates is discussed.
- Zhang, Wei,Kraft, Stefan,Moore, Jeffrey S.
-
p. 329 - 335
(2007/10/03)
-
- A facile and high yielding synthesis of symmetrical and unsymmetrical diarylalkynes using diethyl dichloromethylphosphonate as precursor
-
The reaction, under internal quench conditions, of diethyl dichloromethylphosphonate and symmetrical or unsymmetrical diaryl ketones in the presence of n-BuLi, leads to the corresponding symmetrical or unsymmetrical diarylalkynes via a Fritsch-Buttenherg-Wiechell rearrangement in a simple, high yielding, one-pot reaction.
- Mouriès, Virginie,Waschbüsch, Rachel,Carran, John,Savignac, Philippe
-
p. 271 - 274
(2007/10/03)
-
- Oxidation of Aromatic Compounds. IV. Oxidation of Symmetrical Diarylacetylenes in the CF3COOH-CH2Cl2-PbO2 System. A New One-Pot Synthesis of 1,2,3,4-Tetraaryl-2-butene-1,4-diones
-
Oxidation of symmetrical diarylacetylenes in the CF3COOH-CH2Cl2-PbO2 system (0-20 deg C, 1-3 h) yields 1,2,3,4-tetraaryl-2-butene-1,4-diones.According to (1)H NMR and GC-MS data the compounds synthesized have Z configuration.
- Rudenko, A. P.,Vasil'ev, A. V.
-
p. 1360 - 1379
(2007/10/03)
-
- AN EFFECTIVE OXIDATION OF DIHYDRAZONES TO ACETYLENES WITH COBALT(II) SCHIFF'S BASE COMPLEXES
-
Facile oxidations of dihydrazones of α-diketones to acetylenes were performed with a catalytic amount of bis(salicylidene)ethylenediaminatocobalt(II) and bis(3-methoxysalicylidene)ethylenediaminatocobalt(II) under mild conditions in 88-98percent yields.Keywords---cobalt complex; oxidation; dihydrazone; diarylacetylene; catalytic reaction
- Inada, Akira,Nakamura, Yushin,Morita, Yutaka
-
p. 1041 - 1042
(2007/10/02)
-