A5029472920- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Crystallography and molecular interactions
- Synthesis and characterization of novel inorganic/organometallic compounds
- Organoboron and organosilicon chemistry
- Fluorine in Organic Chemistry
- Organometallic Complex Synthesis and Catalysis
- N-Heterocyclic Carbenes in Organic and Inorganic Chemistry
- Coordination Chemistry and Organometallics
- Catalytic Cross-Coupling Reactions
- Radical Photochemical Reactions
- Chemical Synthesis and Reactions
- Chemical Reactions and Mechanisms
- Inorganic Fluorides and Related Compounds
- Synthesis and Biological Evaluation
- Organophosphorus compounds synthesis
- Sulfur-Based Synthesis Techniques
- Synthetic Organic Chemistry Methods
- Chemical Synthesis and Analysis
- Boron Compounds in Chemistry
- Synthesis and Catalytic Reactions
- Phenothiazines and Benzothiazines Synthesis and Activities
- Boron and Carbon Nanomaterials Research
- Organoselenium and organotellurium chemistry
- Chemical Reaction Mechanisms
University of Toronto
2015-2022
Toronto Public Health
2016-2020
University of Cyprus
2014
University of Windsor
2013
A room-temperature-stable crystalline 2H-phosphirene (1) was prepared by treatment of an electrophilic diamidocarbene with tert-butylphosphaalkyne. Compound 1 is shown to react as a vinylphosphinidene generated via phosphirene–phosphinidene rearrangement. Thermolysis affect C–N bond scission while reactions C6Cl4O2 or (tht)AuCl afford formal oxidation the phosphindene center and phosphinidene-insertion into aromatic C–C mesityl group, respectively. The latter reaction first example...
Single electron transfer (SET) reactions are effected by the combination of a Lewis acid (e.g., E(C6F5)3 E = B or Al) with small molecule substrate and decamethylferrocene (Cp*2Fe). Initially, corresponding (PhS)2 (PhTe)2 were shown to give species [Cp*2Fe][PhSB(C6F5)3] 1 [Cp*2Fe][(μ-PhS)(Al(C6F5)3)2] 2 [Cp*2Fe][(μ-PhTe)(Al(C6F5)3)2] 3, respectively. Analogous di-tert-butyl peroxide yielded [Cp*2Fe][(μ-HO)(B(C6F5)3)2] 4 isobutene while benzoyl afforded [Cp*2Fe][PhC(O)OE(C6F5)3] (E 5, Al 6)....
Abstract A room‐temperature‐stable crystalline cyclic (alkyl)(amino)nitrenium cation 2 features cationic nitrogen atom with a smaller HOMO–LUMO gap compared to that of 1,2,3‐triazolium 5 (an N‐heterocyclic nitrenium cation). The low‐lying LUMO results in an enhanced electrophilicity, which allowed for the formation Lewis adducts neutral bases, such as Me 3 P, n Bu and I i Pr. N‐based acid also forms FLP t P but subsequently reacts (PrS) cleave S−S bond. Both experimental theoretical suggest...
NHC-stabilized parent sulfenyl (H-S+), selenenyl (H-Se+) and tellurenyl (H-Te+) cations have been achieved by treatment of NHC chalcogen adducts with trifluoromethanesulfonic acid. Computational investigations show that most the positive charges are localized at atoms carbene carbons strong donor acceptor interactions between lone pair vacant orbital centre, accounting for its unexpected stability.
The reactions of the cyclic alkyl amino carbene (CAAC) 1 with phosphaalkynes generate kinetically unstable CAAC-derived phosphirenes 4 and 5, which undergo rearrangement/dimerization to give vinyl-substituted diphosphenes 2, 3, 6. P=P double bond scission 2 or 3 is unprecedentedly effected by S8 , [AuCl(tht)], MeOTf at room temperature, affords a dithiophosphorane 7, phosphepine Au complex 8, phosphepinium cations 9 10, respectively. cationic species feature little homoaromaticity while...
Abstract Double chloride abstraction of Cp*AsCl 2 gives the dicationic arsenic species [(η 5 ‐Cp*)As(tol)][B(C 6 F ) 4 ] ( (tol=toluene). This is shown to exhibit Lewis super acidity by Gutmann–Beckett test and fluoride from [NBu ][SbF ]. Species participates in FLP activation THF affording ‐Cp*)AsO(CH (THF)][B(C ). The reaction with PMe 3 or dppe generates [(Me P) As][B(C [(σ‐Cp*)PMe ][B(C 7 ), [(dppe)As][B(C 8 [(dppe)(σ‐Cp*) 9 respectively, through a facile cleavage C−As bonds, thus...
1,3-Diphenylbenzo[e][1,2,4]triazin-7(1H)-one, the oxidation product of 1,3-diphenyl-1,4-dihydro-1,2,4-benzotriazin-4-yl (Blatter's radical), reacts with N′-arylbenzamidines in PhMe at ca. 100 °C presence N,N-diisopropylethylamine (Hünig's base) (1 equiv.) to give N′-aryl-N-(1,7-dihydro-7-oxo-1,3-diphenylbenzo[e][1,2,4]triazin-6-yl)benzimidamides 49–95% yield. In neat AcOH heated 120 °C, N′–aryl-N-(1,7-dihydro-7-oxo-1,3-diphenylbenzo[e][1,2,4]triazin-6-yl)benzimidamides cyclodehydrate novel...
Single electron transfer (SET) reactions are effected by the combination of a Mes<sub>3</sub>P/B(C<sub>6</sub>F<sub>5</sub>)<sub>3</sub> frustrated Lewis pair with benzoyl peroxide derivatives.
The phosphaaluminirenes HC[(CMe)(NDipp)]2Al[C(R)═P] (Dipp = 2,6-i-Pr2C6H3, R tBu or adamantyl) 2 and 3, featuring an unsaturated three-membered AlCP ring, have been synthesized as crystalline solids via a [1 + 2] cycloaddition reaction of the aluminum(I) complex HC[(CMe)(NDipp)]2Al (1) with phosphaalkynes. Computational investigations infer three-centered 2π-electron aromaticity rings. Compound 3 is readily protonated by tBuOH to induce ring-opening σ-bond metathesis, giving...
Reaction of (Idipp)AlH<sub>3</sub> with [Ph<sub>3</sub>C][B(C<sub>6</sub>F<sub>5</sub>)<sub>4</sub>] in toluene affords the dimeric aluminum dication [((Idipp)AlH(μ-H))<sub>2</sub>][B(C<sub>6</sub>F<sub>5</sub>)<sub>4</sub>]<sub>2</sub> corresponding reaction (IBn)AlH<sub>3</sub> gives [(IBn)<sub>2</sub>AlH][B(C<sub>6</sub>F<sub>5</sub>)<sub>4</sub>]<sub>2</sub>.
A cyclic (amino)(aryl)nitrenium cation 2 has been achieved by treatment of spiro[fluorene-9,3'-indazole] (1) with Ph2CHCl and AgBF4. This is Lewis acidic at nitrenium N1, reacting PMe3 affording a acid/base adduct 3. In contrast, deprotonation other bases provides neutral compound 4 which basic electrophiles including GaCl3, MeOTf PhNCO.
Avenues to S-based Lewis acids were developed <italic>via</italic> the oxidation of aryl-sulfoxides with XeF<sub>2</sub>, giving difluorodiarylsulfoxides which react fluoride abstraction afford acidic fluorosulfoxonium cations; this acidity is derived from S–F σ* orbital and has been probed both experimentally computationally.
1-Bora-4-tellurocyclohexa-2,5-diene undergoes sequential [4 + 2] cycloadditions/alkyne-elimination reactions to incorporate 2 equiv of terminal alkyne with the loss diarylalkyne, affording access a series 11 new tellurium-boron heterocycles. These exchange proceed regioselectively and can tolerate variety functional groups, thus providing potential for further derivatization. The mechanism reaction is confirmed by DFT study involve interaction Te B in frustrated Lewis pair fashion transition states.
The neutral doubly base stabilized diborane(4) [C2H2(NCH2C6H4)2CB]2 (3a), featuring an electron-precise B(sp3)–B(sp3) σ bond, was generated by one-electron reduction of the corresponding borenium precursor with Cp*2Co followed dimerization. Compound 3a reacts TEMPO, (PhC(O)O)2, PhNO, (tht)AuCl (tht = tetrahydrothiophene), and S8. resulting species, (C2H2(NCH2C6H4)2CB)(L) (L ONC5H6Me4 (4), OC(O)Ph (5), PhNO (6), Cl (7)) [(C2H2(NCH2C6H4)2CB)2(S4)] (8), have been fully characterized are...
The trityl cation and (<italic>o</italic>-tolyl)<sub>3</sub>P is an FLP that effects C–H bond alkyne activation, heterolytically cleaves S–S bonds captures a Staudinger reaction intermediate.
Abstract A room‐temperature‐stable crystalline cyclic (alkyl)(amino)nitrenium cation 2 features cationic nitrogen atom with a smaller HOMO–LUMO gap compared to that of 1,2,3‐triazolium 5 (an N‐heterocyclic nitrenium cation). The low‐lying LUMO results in an enhanced electrophilicity, which allowed for the formation Lewis adducts neutral bases, such as Me 3 P, n Bu and I i Pr. N‐based acid also forms FLP t P but subsequently reacts (PrS) cleave S−S bond. Both experimental theoretical suggest...
The phosphepinium cation 1 is deprotonated by base generating a phosphaalkene that undergoes cycloaddition to the N-bound aromatic ring affording 2-phosphabicyclo[2.2.2]octa-5,7-diene 2. analogous deprotonation reaction of less bulky 3 affords reversible equilibrium between 4 and corresponding product 5. This latter observation represents first main group multiply bonded species with an arene ring. bicyclic 2 was also shown be oxidized or alkylated in reactions S8 MeOTf, 6 7, respectively....
While (Ph
Double chloride abstraction from Cp*SbCl2 (Cp* = pentamethylcyclopentadienyl) affords an arene-stabilized η5-Cp*-bound antimony dicationic compound [(η5-Cp*)Sb(tol)][B(C6F5)4]2 (1) (tol toluene), which exhibits strong Lewis acidity, abstracting Ph3CCl. 1 reacts with different bases via divergent pathways, giving rise to release of either Sb+ or Sb3+ cations.
The salts [(BAC)2 PO][BF4 ] (5) and PO2 ][BF4 (4) (BAC=bis(diisopropylamino) cyclopropenylidene), consisting of the PO+ PO2+ cations, respectively, coordinated to singlet carbenes, have been prepared. Computational investigations reveal that electronic structure cation is a hybrid between charge-localized charge-delocalized resonance forms, resulting in ambiphilic reactivity. Compound 5 reacts as donor with transition-metal complex K2 PtCl4 furnish [[(BAC)2 PO]2 PtCl2 ]2 (6) KCl. Remarkably,...
The reductive coupling of two diazomethanes is affected by reaction with [(NacNacMes )Mg]2 affording the species )Mg(N2 CPh2 )]2 2 and C(C6 H4 )2 3. These containing N4 linkages readily evolve central N2 at 50 75 °C to give Mg-imide products )Mg(NCPh2 (4) )Mg(NC(C6 (5), respectively. mechanism for loss was considered computationally. Compounds 3 reacted O2 liberate tetrazene (Ph2 6 hydrazine ((C6 CN)2 7, whereas reactions Me3 SiOSO2 CF3 or SiCl provide related silyl imines 8 9,
Varying the reaction ratio of cyclic (alkyl)(amino) carbene (cAAC<sup>Et</sup>) with AlH<sub>3</sub>·NEtMe<sub>2</sub> leads to isolation (cAAC<sup>Et</sup>H)AlH<sub>2</sub>·NEtMe<sub>2</sub><bold>1</bold> and (cAAC<sup>Et</sup>H)<sub>2</sub>Al(μ-H)<sub>2</sub>AlH<sub>2</sub>·NEtMe<sub>2</sub><bold>2</bold> first example a monomeric dialkyl-aluminum hydride (cAAC<sup>Et</sup>H)<sub>2</sub>AlH <bold>3</bold>.
Abstract Double chloride abstraction of Cp*AsCl 2 gives the dicationic arsenic species [(η 5 ‐Cp*)As(tol)][B(C 6 F ) 4 ] ( (tol=toluene). This is shown to exhibit Lewis super acidity by Gutmann–Beckett test and fluoride from [NBu ][SbF ]. Species participates in FLP activation THF affording ‐Cp*)AsO(CH (THF)][B(C ). The reaction with PMe 3 or dppe generates [(Me P) As][B(C [(σ‐Cp*)PMe ][B(C 7 ), [(dppe)As][B(C 8 [(dppe)(σ‐Cp*) 9 respectively, through a facile cleavage C−As bonds, thus...