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In this chapter, Eric Fillion discusses how rock and the rockumentary can be used for purposes of nation building through the case of Quebecois politics and the progressive rock band Harmonium and the rockumentary Harmonium in California.

Density functional theory (DFT) calculations and infrared multiple photon dissociation (IRMPD) spectroscopy are employed to probe [TM·(B12H12)]− and [TM·(B12H12)2]2– clusters [TM = Ag(I), Cu(I), Co(II), Ni(II), Zn(II), Cd(II)]. A comparison is made between the charge-transfer properties of the clusters containing the hydrogenated dodecaborate dianions, B12H122–, and the fluorinated analogues, B12F122–, for clusters containing Cd(II), Co(II), Ni(II), and Zn(II). IRMPD of the [TM·(B12H12)]− and [TM·(B12H12)2]2– species yields B12H11– via hydride abstraction and B12H12– in all cases. To further explore the IR-induced charge-transfer properties of the B12X122– (X = H, F) cages, mixed-cage [TM(B12H12)(B12F12)]2– [TM = Co(II), Ni(II), Zn(II), Cd(II)] clusters were investigated. IRMPD of the mixed-cage species yielded appreciable amounts of B12F12– and B12H12– in most cases, indicating that charge-transfer to the central TM cation is a favorable process; formation of B12F12– is the dominant process for the Co(II...

Clusters of all-cis 1,2,3,4,5,6-hexafluorocyclohexane and the dodecafluorododecaboron dianion, [C6F6H6]n[B12F12]2– (n = 0–4), are investigated in a combined experimental and computational study. DFT calculations and IRMPD spectra in the region of 800–2000 cm–1 indicate that C6H6F6 binds to open trigonal faces of B12F122– via a three-point interlocking binding motif. Calculated binding interactions reveal substantial contributions from C–H···F hydrogen bonding and binding energies that are among the strongest observed for a neutral-anion system.

Infrared multiple photon dissociation spectra of the proton-bound heterodimers of phenylalanine/glycine (Phe·H + ·Gly) and pentafluorophenylalanine/glycine (F 5 -Phe·H + ·Gly) have been acquired in the 975–1975 cm −1 region. Exhaustive basin hopping molecular dynamics searches and subsequent DFT calculations predict four low energy intermolecular binding motifs. The spectrum of F 5 -Phe·H + ·Gly is assigned predominantly to isomers exhibiting a N H + ⋯O intermolecular interaction between nitrogen-protonated Gly and the carbonyl oxygen atom of F 5 -Phe. In contrast, the spectrum Phe·H + ·Gly is found to consist of a mixture of isomers exhibiting the N H + ⋯O between nitrogen-protonated Gly and the carbonyl oxygen of neutral Phe, and isomers exhibiting a N H + ⋯N interaction between nitrogen-protonated Phe and the neutral Gly moiety. Cation-π effects also seem to influence the cluster geometries, especially in the case of the Phe·H + ·Gly global minimum structure where the phenyl ring orients with the site of protonation so as to maximize charge-quadrupole interactions.

The modification of benzylic quaternary, tertiary, and secondary carbon centers through palladium-catalyzed hydrogenolysis of C(sp3)–C(sp3) σ bonds is presented. When benzyl Meldrum's acid derivatives bearing quaternary benzylic centers are treated under mild hydrogenolysis conditions – palladium on carbon and atmospheric pressure of hydrogen – aromatics substituted with tertiary benzylic centers and Meldrum's acid are obtained with good to excellent yield. Analogously, substrates containing tertiary or secondary benzylic centers yield aromatics substituted with secondary benzylic centers or toluene derivatives, respectively. Furthermore, this strategy is used for the high yielding synthesis of diarylmethanes. The scope of the reductive dealkylation reaction is explored and the limitations with respect to steric and electronic factors are determined. A mechanistic analysis of the reaction is described that consisted of deuterium labelling experiments and hydrogenolysis of enantioenriched derivatives. The investigation shows that the C(sp3)–C(sp3) σ bond-cleaving events occur through a hybrid SN1/SN2 mechanism, in which the palladium center displaces a carbon-based leaving group, namely Meldrum's acid, with inversion of configuration, followed by reductive elimination of palladium to furnish a C−H bond.

Density functional theory (DFT) calculations and infrared multiple photon dissociation (IRMPD) spectroscopy are employed to probe [TM·(B

Tris(pentafluorophenyl)borane, B(C6F5)3, has been found to be an effective catalyst to access the hydridoborate anion, [N(CH2CH2CH2)3Sn][HB(C6F5)3], via hydride abstraction from the hypercoordinated tin reagent, iPr-tricarbastannatrane. This process has been applied to the B(C6F5)3-catalyzed transfer 1,4-hydrostannylation of electron-deficient olefins, namely benzylidene barbituric acids. Insights into the mechanism have been obtained via a series of 1H, 2H, 11B, 13C, and 119Sn NMR spectroscopy, mass spectrometry, and labeling experiments.

Fonde en 1967, le Jazz libre se demarque dans le paysage culturel du Quebec par sa quete d’une praxis revolutionnaire dont la visee est de promouvoir la democratie culturelle dans les milieux ouvriers. Durant ses huit annees d’existence, ce groupe d’improvisateurs tisse des liens non negligeables avec le Conseil central des syndicats nationaux de Montreal, le Front de liberation du Quebec et le Front de liberation des femmes. Les membres de ce collectif s’approprient le free jazz – une musique rattachee au nationalisme noir – afin de situer leur projet d’un Quebec socialiste et independant dans un processus historique marque par la decolonisation. Cette appropriation exprime un desir de concretiser un rapprochement entre l’individu quebecois colonise – celui que Pierre Vallieres qualifie de « negre blanc d’Amerique » – et son homologue afro-americain. Elle repose sur la conviction que l’improvisation en musique est un vecteur de communication, d’organisation et de participation. La presente etude interroge le discours politico-culturel sur lequel la « musique-action » du Jazz libre repose. Elle propose une analyse elargie de la place occupee par le free jazz dans les mouvements de resistance au pouvoir tout en mettant en relief le volet culturel du militantisme politique deploye au Quebec durant les annees 1960 et 1970. Abstract: Founded in 1967, Free Jazz stands in the cultural landscape of Quebec by its quest for a revolutionary praxis which aims to promote cultural democracy among workers. During its eight years of existence, this group of improvisers weaves significant links with the Montreal Council of the Confederation of National Trade Unions, the Quebec Liberation Front and the Women’s Liberation Front. Members of this group appropriated Free Jazz – a music attached to black nationalism – in order to insert their project of a socialist and independent Quebec in a historical process marked by decolonization. This appropriation expressed a desire to achieve a rapprochement between the colonized individual Quebecker – Pierre Vallieres, whom one calls “white negro in America” – and his African-American counterpart. It was based on the belief that musical improvisation is a vehicle for communication, organization and participation. This study questions the political and cultural discourse on which the “music-action” of Free Jazz was based. It offers a broader analysis of the place of Free Jazz in resistance movements while highlighting the cultural aspect of political activism in Quebec during the 1960s and 1070s.

A combination of infrared multiple photon dissociation (IRMPD) spectroscopy and density functional theory calculations is used to investigate the structures and charge-transfer properties of clusters containing transition metals (TM = Co(II), Ni(II), Cu(I), Zn(II), Rh(III), Pd(II), Ag(I), Cd(II)) and the dodecafluorododecaboron dianion, B12F122–. In all cases, IRMPD resulted in transfer of electron density to the metal center and production of B12F12–. Metals that exhibit the highest degree of charge transfer are found to induce reaction among the B12F12 cages, leading to production of BnFm (up to n = m = 24).

The synthesis and characterization of a series of tricarbastannatranes, in the solid state and in solution, are described. The structures of the complexes [N(CH2 CH2 CH2 )3 Sn](BF4 ), [N(CH2 CH2 CH2 )3 Sn](SbF6 ), [N(CH2 CH2 CH2 )3 Sn]4 [(SbF6 )3 Cl], and [(N(CH2 CH2 CH2 )3 Sn)2 OH][MeB(C6 F5 )3 ] were determined by X-ray crystallography. Furthermore, the B(C6 F5 )3 -promoted conjugate addition of alkyl-tricarbastannatranes to benzylidene derivatives of Meldrum's acid was investigated, and detailed mechanistic studies are presented.

It is generally assumed that molecules behave ergodically during chemical reactions, that is, reactivities depend only on the total energy content and not on the initial state of the molecule. While there are a few examples of nonergodic behavior in small (usually electronically excited) species, to date there have been no reports of such behavior in larger covalently bound species composed of several tens of atoms. Here, we demonstrate vibrational mode-selective behavior in a series of palladium catalysts. When we excite solvent-tagged gas-phase Pd catalysts with an infrared laser that is tuned to be resonant with specific molecular vibrations, depending on which vibration we excite, we can select different reaction pathways. We also demonstrate that this behavior can be “turned off” via chemical substitution.

Clusters of all-cis 1,2,3,4,5,6-hexafluorocyclohexane and the dodecafluorododecaboron dianion, [C

The structures and properties of a series of phenylalanine (Phe) derivatives have been investigated in a joint computational and experimental infrared multiple photon dissociation (IRMPD) study. IRMPD spectra in the 1000–2000 cm−1 region show that protonation is localized on the amine group in all cases. Intramolecular cation–π interactions between the ammonium group and the phenyl ring heavily influence molecular geometries and properties such as gas phase basicity and proton affinity. By varying substituents on the phenyl ring, one can sensitively tune the cation–π interaction and, therefore, the molecular structure and properties. Variations in molecular structures and properties as a function of phenyl ring substitution are shown to correlate with substituent Hammett parameters.

Tris(pentafluorophenyl)borane, B(C

Hypercoordinated complexes involving tricarbastannatrane cation [N(CH2CH2CH2)3Sn]+ with various Lewis bases are investigated in the gas and solution phases using a combination of infrared multiple photon dissociation (IRMPD) spectroscopy, NMR spectroscopy, and density functional theory calculations. Coordination is found to occur at the apical position leading to a pentacoordinated Sn center. Strongly electron donating Lewis bases disrupt the N···Sn transannular interaction and induce higher degrees of geometric distortion at the metal center than weakly donating Lewis bases, an effect that manifests as anharmonic shifts in the vibrational spectra. Once characterized in the gas phase, [N(CH2CH2CH2)3Sn(Lewis base)]+ structures were embedded in a dichloroethane polarizable continuum model to investigate solution phase properties. Calculated 119Sn NMR chemical shifts were found to be in good agreement with those measured experimentally, thus suggesting that the bonding properties of [N(CH2CH2CH2)3Sn]+ are es...

The authors acknowledge support in the form of NSERC (Canada) Discovery Grants to EF, WSH, and TBM and an EPSRC (UK) responsive mode grant to DO’H and NSK is gratefully acknowledged. Experiments have been carried out in which electrospray ionization has been used to generate ionic complexes of all-cis 1,2,3,4,5,6 hexafluorocyclohexane. These complexes were subsequently mass isolated in a quadrupole ion trap mass spectrometer and then irradiated by the tunable infrared output of a free electron laser in the 800-1600 cm−1 range. From the frequency dependence of the fragmentation of the complexes, vibrational signatures of the complexes were obtained. Computational work carried out in parallel reveals that the complexes formed are very strongly bound and are among the most strongly bound complexes of Na+ and Cl− ever observed with molecular species. The dipole moment calculated for the heaxafluorocyclohexane is very large (~7 D) and it appears that the bonding in each of the complexes has a significant electrostatic contribution. Postprint

Under Sc(OTf)3 catalysis, benzylidene Meldrum’s acids bearing a tethered p-methoxyphenethyl group were observed to undergo a [1,5]-hydride shift/cyclization at room temperature, representing a mild Csp3–H bond functionalization. The resulting spiro Meldrum’s acid intermediates then underwent intramolecular Friedel–Crafts acylation, completing the one-pot, domino reaction. The reported protocol generates the 6-6-5-6 tetracyclic core of tetrahydrobenzo[b]fluoren-11-ones.

The intramolecular Friedel–Crafts acylation of arenes with Meldrum's acid derivatives catalyzed by Sc(OTf)3 was reported as a mild and general entry into functionalized 1-indanones. Mechanistic investigations were undertaken to determine the rate-determining step in the acylation sequence using Meldrum's acid, as well as to examine the role of the Lewis acid catalyst. Enolizable Meldrum's acid derivatives react via an acyl ketene intermediate under thermal conditions, while quaternized Meldrum's acid derivatives are thermally stable and only act as effective Friedel–Crafts acylating agents in the presence of a Lewis acid catalyst. The acylation was postulated to proceed through direct acylation of a Lewis acid-activated carbonyl. In the catalytic Friedel–Crafts acylation of Meldrum's acids, triflic acid appeared to be the active catalytic species, with Sc(OTf)3 serving as a very mild and convenient reagent for its delivery.

The asymmetric formation of all-carbon quaternary benzylic stereocenters containing a methyl substituent was realized by the enantioselective copper-catalyzed 1,4-addition of dimethylzinc to alkylidene Meldrum's acids in the presence of a chiral phosphoramidite. Copper source and ligand optimization studies are presented, as well as the scope and limitations of dimethylzinc addition to various alkylidene Meldrum's acids. Good to excellent yields and enantioselectivities were obtained.

A full account of the Pd-catalyzed intramolecular reactions of (E)-2,2-disubstituted 1-alkenyldimethylalanes with aryl triflates as an entry into polycarbocyclic structures displaying an ethyl−methyl-substituted all-carbon benzylic quaternary center is herein presented. It was found that the efficiency of the Pd-catalyzed carbon−carbon bond forming process is highly affected by the structure of the starting material, including tether length and aryl substitution pattern; substituting the position ortho to the triflate is mandatory to obtain a good yield of the carbocycle. Moreover, the formation of 1-ethyl-1-methylindanes is facile in comparison to the case for the analogous tetrahydronaphthalenes, for which the competing methyl cross-coupling reaction is equally competent. It was established through labeling studies that the carbon−carbon bond forming events are stereospecific and proceed though the intermediacy of a neopentylic sp3-gem-dimetallic palladio(II) dialkylaluminoalkane species, from which a 1...

Alkylidene Meldrum's acids are allylated in a conjugate fashion by allyltin nucleophiles under mild Sc(OTf)(3)-catalyzed conditions. The addition is functional group tolerant and reactions with nonracemic alkylidenes are highly diastereoselective. Allylation of alkylidenes derived from alpha-ketoesters yield all-carbon quaternary stereocenters.

Persistent intramolecular interactions between acidic C-H hydrogens and a variety of acceptors (X) (X = O, S, Br, Cl, and F) in solution were probed by (1)H NMR experiments, using 5-benzyl Meldrum's acid derivatives. To bring about formation of intramolecular C-H...X bonding, ortho-substituted benzyl Meldrum's acids were designed, for which hydrogen bonding occurred through a six-membered ring. Introduction of substituents on the aromatic moiety and in the tether allowed variation of electronic and steric factors. The superior acidity of Meldrum's acids impacted the ability of the C-H hydrogen to engage in nonclassical C-H...X bonds and drove the conformational properties of benzyl Meldrum's acid, in combination with steric factors, namely A(1,3)-allylic strain. Further understanding of intramolecular C-H...X bonds was gained by characterization of benzyl Meldrum's acids in the solid state, by X-ray analysis, and by the conformation correlated to the observations made in solution.

The ability to tune the reactivity of palladium carbenes derived from diphenylketene, which is dependent on the oxidation state of the metal center, is presented. Competition experiments illustrated that Pd(0) catalysts favor direct C−H functionalization of terminal alkynes and that Pd(II) catalysts lead to cyclopropanation of strained alkenes. In addition, a PdCl2-catalyzed cyclopropane isomerization of diphenylcyclopropanes and an unprecedented Pd(II)-catalyzed domino cyclopropanation/isomerization reaction are described.

4-Substituted indoles containing a variety of electrophiles and N-substituents undergo Friedel-Crafts acylation to give exclusively the products of cyclization at the 5-position of indole. These indanones and tetralones have been scarcely prepared and are subunits in natural products and analogues of potential biological significance.

The rhodium-catalyzed conjugate addition of functionalized vinyltin reagents to alkylidene Meldrum's acids, followed by Pd-catalyzed intramolecular allylation, is a direct entry into vinyl-substituted gamma-lactones via O-alkylation and vinylcyclopropanes via C-alkylation.

The conjugate addition reaction of metal alkynylides to Meldrum′s acids gives access to derivatives (III) and (VI) having a propargylic all-carbon quaternary center.

The one-pot synthesis of tetrahydrofluorenones, the core 6-5-6 tricyclic structural motif found in norditerpenoid natural products, from alkylidene Meldrum's acids via thermal Diels-Alder/BF3.OEt2-catalyzed Friedel-Crafts acylation reactions is described. A series of tetrahydrofluorenones was assembled in good yields, and the Diels-Alder/Friedel-Crafts acylation protocol allowed modification of the substitution within the rings.

[reaction: see text] The Yb(OTf)3-catalyzed annulation reactions of phenols with 5-alkylidene Meldrum's acids enabled the synthesis of structurally diverse heterocycles in high isolated yields. A series of 4-substituted 3,4-dihydrocoumarins, 2,2-disubstituted 4-chromanones, coumarins, and 2-substituted chromones were readily and efficiently assembled, including the naturally occurring coumarins citropten, scoparone, and ayapin. Addition of phenols to biselectrophilic 5-alkylidene Meldrum's acids proceeded through two distinct multibond-forming modes: Friedel-Crafts C-alkylation/O-acylation and Friedel-Crafts C-acylation/O-alkylation. The regioselectivity of the catalytic annulation reaction was controlled by the degree of substitution on the alkylidene moiety.

The conjugate alkynylation of alkylidene Meldrum’s acids with alkynylalanes and alkynyl Grignards allows for the formation of propargylic all-carbon quaternary stereocenters in high yields. Ag2CO3-catalyzed intramolecular cyclization of propargylic Meldrum’s acid derivatives offers a two-step entry into complex γ-alkylidene butyrolactones containing an all-carbon quaternary center at the C-4 position.

C–H···X (where X = O or S) intramolecular hydrogen bonding is investigated in three benzyl Meldrum’s acid derivatives using a combination of solution phase NMR spectroscopy, gas phase infrared multiple photon dissociation spectroscopy, and density functional theory calculations. In one compound, an abnormally large C–H···S hydrogen bond energy of 30.4 kJ mol–1 is calculated with a natural bond orbital analysis. Intramolecular C–H···O hydrogen bonding is found to persist in the gas phase. Gibbs energy decomposition pathways are calculated.

Although many methods have been reported for the Knoevenagel condensation of aldehydes and Meldrum’s acid, most are not general or use unconventional reagents and conditions. We have found that alkylidene Meldrum’s acids form readily in benzene solution under mild pyrrolidinium acetate catalysis, and that this reaction is general, highly functional group compatible, and can be scaled-up easily.

Unsymmetrical 8-oxa-3-thiabicyclo[3.2.1]octane and 9-oxa-3-thiabicyclo[3.3.1]nonane underwent highly regioselective base-induced elimination but low selectivity was observed for the sulfonyl and the aza-oxa systems. A correlation between the regioselectivity of the reaction and the proton undergoing abstraction (i.e. equatorial vs. the axial proton) was made.

The ambiphilic vinylcarbenoid reactivity of (α-(tributylstannyl)-π-allyl)palladium(II) species is demonstrated by the reaction of acetoxystannanes with Pd(dba)2, which promotes electrophilic metal−carbene reactions such as dimerization and cyclopropanation of strained alkenes. On the other hand, Pd(PPh3)4 and dppe revealed the nucleophilic nature of the dimetallic intermediates through sequential reactions of the carbon−metal bonds with dimethyl malonate.

The asymmetric synthesis of tertiary and quaternary stereocentres has been successfully achieved through Cu-catalyzed 1,6-addition of dialkylzinc reagents to 5-(3-aryl-2-propenylidene) Meldrum’s acid derivatives in the presence of a phosphoramidite ligand.

(5-Chloro-1-aza-5-stannabicyclo[3.3.3]undecane) [93253-73-7] C9H18ClNSn (MW 294.41) InChI = 1S/C9H18N.ClH.Sn/c1-4-7-10(8-5-2)9-6-3;;/h1-9H2;1H;/q;;+1/p-1 InChIKey = BRPCJQRIZVVNKX-UHFFFAOYSA-M (precursor to organostannatranes that enable facile transfer of apical group due to intramolecular activation; selective alkyl transfer agent precursor) Alternate Name: 1-aza-5-chloro-5-stannabicyclo[3.3.3]undecane. Physical Data: mp 236–238 °C (EtOH),1 222–224 °C (MeOH).2 Solubility: soluble in Et2O, THF, EtOAc, CH2Cl2, and hexanes; slightly soluble in MeCN, MeOH, and i-PrOH; insoluble in H2O and aq. HCl. Form Supplied in: commercially available solid. Analysis of Reagent Purity: 13C and 119Sn NMR.3 Preparative Methods: initially prepared by transmetalation of N(CH2CH2CH2MgCl)34, 5 with SnCl4 in 12–15% yield. Subsequently, hydrozirconation of N(CH2CH–CH2)3 with Cp2ZrHCl followed by transmetalation with SnCl4 furnished 5-chloro-1-aza-5-stannabicyclo[3.3.3]undecane in 50% yield.2 Alternatively, 5-chloro-1-aza-5-stannabicyclo[3.3.3]undecane is prepared in 40% yield from N(CH2CH2CH2SnMe3)3 by thermal redistribution with Me2SnCl2.1, 5 N(CH2CH2CH2SnMe3)3 is synthesized by reacting N(CH2CH2CH2Cl)3 with Me3SnNa in liquid ammonia at −78 °C. Drawbacks to the preparation of chlorostannatrane by these routes are low yields, handling of volatile methyltin derivatives, harsh conditions, and/or expensive reagents. A scalable, two-step synthesis that remedies the former issues consists of the thermal redistribution of N(CH2CH2CH2SnBu3)3 with SnCl4 (eq 1). The tributylstannane N(CH2CH2CH2SnBu3)3 is accessible in 66% yield by the Pd/Al2O3-catalyzed hydrostannation of N(CH2CHCH2)3 with Bu3SnH, or alternatively, by the substitution of N(CH2CH2CH2Cl)3 with Bu3SnLi in 78% yield.6 (1) Purification: acid/base extraction6 or recrystallization from MeOH.2 Handling, Storage, and Precautions: toxic by ingestion and is a skin, eye, and respiratory tract irritant.7