The coordination chemistry of a structurally rigid phosphine–thioether–borane ligand, TXPB (TXPB = 2,7-di-tert-butyl-5-diphenylboryl-4-diphenylphosphino-9,9-dimethylthioxanthene), as well as the Group 13 Lewis acid-appended analogues of 1,1'-bis(phosphino)ferrocene, FcPPB (FcPPB = [Fe(η5-C5H4PPh2){η5-C5H4PtBu(C6H4BPh2-o)}]) and FcPPAl (FcPPAl = [Fe(η5-C5H4PPh2){η5-C5H4PtBu(C6H4AlMe2-o)}]) has been explored with a range of transition metal pre-cursors. Previously reported [Rh(μ-Cl)(CO)(TXPB)] (1) reacted with Me3SiBr, Me3SiI, [NMe4]F, Tl[PF6] and NaBH4 to provide [Rh(μ-Br)(CO)(TXPB)] (2), [RhI(CO)(TXPB)] (3), [Rh(CO)(TXPB-F)] {(4); TXPB-F = {5-(2,7-di-tert-butyl-4-diphenylphosphino-9,9-dimethylthioxanthenyl)}diphenylfluoroborate]}, [Rh(CO)(TXPB)][PF6] (5) and [Rh(μ-H)(CO)(TXPB)] (6), respectively; the rhodium–borane and rhodium–co-ligand–borane coordination modes within these complexes are dependant on the co-ligand bound to rhodium (co-ligand = Cl, Br, I, F, H, or none in the case of cationic 5). Additionally, previously reported [(TXPB)Rh(μ-CO)2Fe(CO)Cp] (7) reacted with various isonitriles (CNR; R = C6H4Cl-p, 2,6-Me2-C6H3, nBu) to yield the bridging borataaminocarbyne complexes [(TXPB)Rh(μ-CO)(μ-CNR)Fe(CO)Cp] (8–10). The borane-free analogue of (7), [(TXPH)Rh(μ-CO)2Fe(CO)Cp] (11; TXPH = 2,7-di-tert-butyl-4-diphenylphosphino-9,9-dimethylthioxanthene), was synthesized for comparison, and reacted with CNC6H4Cl-p to yield [(TXPH)Rh(CO)(μ-CNC6H4Cl-p)2Fe(CO)Cp] (12), featuring two bridging isonitrile ligands. The TXPB ligand reacted with [PtMe2(cod)] (cod = 1,5-cyclooctadiene), forming [PtMePh(TXPB')] (13; TXPB' = 2,7-di-tert-butyl-5-methylphenylboryl-4-diphenylphosphino-9,9-dimethylthioxanthene), which exists in equilibrium with zwitterionic [PtMe(TXPB-Me)] (13') in solution. When heated, [PtMePh(TXPB')] (13) was converted to [PtPh2(TXPB'')] (14; TXPB'' = 2,7-di-tert-butyl-5-dimethylboryl-4-diphenylphosphino-9,9-dimethylthioxanthene) as an 86:14 equilibrium mixture with 13. Moreover, [PtMePh(TXPB')] (13) reacted with PPh3 and P(OPh)3 to provide neutral [PtMePh(PR3)(TXPB')] [R = Ph (15), OPh (16)], or with CNXyl to yield zwitterionic [PtMe(CNXyl)2(TXPB-Me)] (17; TXPB-Me = {5-(2,7-di-tert-butyl-4-diphenylphosphino-9,9-dimethylthioxanthenyl)}methyldiphenylborate). To address several limitations with the TXPB ligand, a new borane-containing ambiphilic ligand, FcPPB (26), was prepared in a seven step convergent synthesis from commercially available ferrocene and 1,2-dibromobenzene. The FcPPB ligand reacted with the Group 10 metal pre-cursors [Ni(cod)2], [Pd2(dba)3] (dba = trans,trans-dibenzylideneacetone) and [Pt(nb)3] (nb = norbornene), yielding co-ligand free [M(FcPPB)] complexes [M = Ni (28), Pd (29), Pt (30)] exhibiting κ2PP- and η3BCC-coordination of the FcPPB ligand. Alternatively, a trisphosphine-analogue of FcPPB, FcPPP (FcPPP = [Fe(η5-C5H4PPh2){η5-C5H4PtBu(C6H4PPh2-o)}]) (25), reacted with [Ni(cod)2] and [Pd2(dba)3] to form [{Ni(FcPPP)}2(μ-N2)] (33) and [Pd(η2-dba)(FcPPP)] (34), respectively. Platinum complex 30 reacted with CO, CNXyl and H2, providing [Pt(CO)(FcPPB)] (35), [Pt(CNXyl)(FcPPB)] (36) and [PtH(μ-H)(FcPPB)] (37), in which the borane is no longer η3BCC-coordinated; the arylborane in FcPPB is now engaged in η2BC-, η1B- and bridging Pt–H–B coordination, respectively. Moreover, [Pt(FcPPB)] (30) reacted with PhC2H to provide [Pt(C2Ph)(μ-H)(FcPPB)] (38), which rapidly isomerized to the vinylborane complex, [Pt(FcPPB')] (39; FcPPB' = [Fe(η5-C5H4PPh2)(η5-C5H4PtBu{C6H4BPh(CPh=CHPh-Z)-o})]). The FcPPB ligand also reacted with [Au(PPh3)][GaCl4] to yield [{Au(FcPPB)}2][GaCl4] (40) as a diastereomeric mixture, or with [W(CO)6] and [Ru3(CO)12] under photochemical and thermal conditions, respectively, to yield [W(CO)4(FcPPB*)] (41; FcPPB* = [Fe(η5-C5H4PPh2){η5-C5H3P(tBu)C6H4BPh-o}]) and [Ru3(μ-H)(CO)10(FcPPB**)] (42; FcPPB** = [Fe(η5-C5H4PPh2){η5-C5H3P(tBu)C6H4BPh2-o}]–), respectively. Both [W(CO)4(FcPPB*)] (41) and [Ru3(μ-H)(CO)10(FcPPB**)] (42) are products of intramolecular attack of the borane on the adjacent cyclopentadienyl-ring. Free FcPPB did not undergo any reaction under similar conditions. However, FcPPB reacted with B(C6F5)3 and BF3·OEt2 to yield FcPPB{B(C6F5)3} (43; [Fe(η5-C5H4PPh2{B(C6F5)3}){η5-C5H4PtBu(C6H4BPh2-o)}]) and [FcPPB-Ph][BF4] (44; [Fe(η5-C5H4PPh2){η5-C5H4PtBu(C6H4BPh-o)}]+), respectively; the former is a phosphine–borane adduct, whereas the latter is a bisphosphine-stabilized boronium cation. The coordination chemistry of a dimethylalane-appended analogue of FcPPB, FcPPAl (27), was also investigated; reaction with [Pt(nb)3] provided [Pt(η2-nb)(FcPPAl)] (45), which readily reacted with C2H4, C2Ph2, H2, and CO to provide [Pt(η2-C2H4)(FcPPAl)] (47), [Pt(η2-C2Ph2)(FcPPAl)] (48), [PtH2(FcPPAl)] (49) and [Pt(CO)(FcPPAl)] (50), respectively. Alternatively, heating a benzene solution of [Pt(η2-nb)(FcPPAl)] (45) yielded co-ligand free [{Pt(FcPPAl)}2] (46). All of the isolated platinum-FcPPAl complexes feature κ3PPAl-coordination of the FcPPAl ligand to platinum, and are the first unambiguous examples of η1Al-coordinated alkylalane complexes. / Thesis / Doctor of Philosophy (PhD) / Ambiphilic ligands are defined as ligands which contain both conventional Lewis basic donors and unconventional Lewis acidic moieties, and the focus of this thesis is to expand the transition metal chemistry of Group 13 Lewis acid-containing ambiphilic ligands. This work expands the knowledge base of fundamental coordination and organometallic chemistry by exploring the effects of ambiphilic ligands on the structures, stability and reactivity of the resulting late transition metal complexes. Three different ambiphilic ligand systems have been employed in this research (TXPB, FcPPB and FcPPAl), which vary either by the structural rigidity of the ligand backbone (TXPB = thioxanthene; FcPPB and FcPPAl = ferrocene), the donor groups available to bind to the metal centre (TXPB = phosphine/thioether; FcPPB and FcPPAl = phosphine/phosphine), or the identity of the appended Lewis acid (TXPB and FcPPB = aryldiphenylborane; FcPPAl = aryldimethylalane). These ligands have provided access to a wide variety of metal–Lewis acid and metal–co-ligand–Lewis acid bonding interactions and novel reaction pathways with small molecules, some of which are relevant to the future development of unique cooperative and catalytic reactivity.

Ce manuscrit présente la synthèse, la réactivité et les propriétés des amino(organo)boranes. Le diisopropylaminoborane a été utilisé dans le cadre de la formation de liaisons carbone-bore. La réactivité du diisopropylaminoborane en tant qu’agent de borylation a d’abord été mise à profit pour l’hydroboration des alcynes catalysée par le réactif de Schwartz. Une grande variété d’alcénylaminoboranes, -boronates et -diazaborolanes a ainsi été synthétisée. Leur transformation stéréosélective en bromoalcènes Z et E a également été optimisée. La borylation des alcynes vrais via un procédé tandem de déshydrogénation / couplage déshydrogénant a permis l’accès à une grande variété d’alcynylaminoboranes. Enfin, les différentes réactivités des aminoboranes ont été mises à profit dans la préparation d’acides boriniques comportant une fonction phosphine, ainsi que d’ une nouvelle classe de dérivés du bore chiraux par atropoisomérie autour de la liaison C-B. Ces aminoarylboranes chiraux ont été caractérisés par séparation des énantiomères complétée d’études spectroscopiques et de racémisation. / This manuscript presents the synthesis, reactivity and properties of amino(organo)boranes. The diisopropylaminoborane has been used for the formation of carbon-boron bonds. Its reactivity as a borylating agent was first explored for the hydroboration of alkynes catalyzed by Schwartz reageant. A large variety of alkenylaminoboranes, -boronates and -diazaborolanes was thus synthesized. Their stereoselective transformation into E and Z bromoalkenes was also optimized. The borylation of terminal alkynes via a tandem process of dehydrogenation/ dehydrogenative coupling allowed the access to a large scope of alkynylaminoboranes. Finally, the different reactivities of aminoboranes were used for the preparation of borinic acids bearing a phosphine group but also of a new class of chiral boron derivatives via a C-B atropisomerism. These chiral aminoarylboranes were fully characterized after separating the enantiomers and running spectroscopic analyses and racemization studies.

Après avoir pu développer une nouvelle méthode de déracémisation de biphényles iodés permettant, pour la première fois, d’influencer la diastéréosélectivité de la réaction de piégeage du réactif d’Andersen par dédoublement cinétique, nous avons obtenu de nombreuses informations et développé des méthodes permettant de lever différents verrous synthétiques pour accéder à des paires de Lewis frustrées basées sur le squelette biphénylique et portant simultanément ou non un groupement acide de Lewis et une base de Lewis. Par la fonctionnalisation de ces biphényles, nous avons pu accéder à de nouvelles biphénylphosphines énantiopures pouvant jouer le rôle de base de Lewis dans le domaine des paires de Lewis frustrées (FLP) mais aussi d'organocatalyseur nucléophile ou de ligand pour la catalyse organométallique. Différentes méthodes ont ensuite été (re)développées, pour accéder à des acides de Lewis : d'une part la synthèse de boranes par fonctionnalisation de sels d'organotrifluoroborate de potassium comme précurseurs polyvalents d’acides de Lewis chiraux et énantiopurs et d'autre part l’utilisation de silanes électrophiles. L’ensemble des informations et méthodes découlant de ce travail pourront être appliquées à la synthèse de molécules ambiphiles, nouvelles paires de Lewis atropo-frustrées. / After having developed a new method of deracemization of iodinated biphenyls allowing us, for the first time, to influence the diastereoselectivity of the trapping by the Andersen reagent, we have turned our attention to the use of this molecular scaffold in the design of new frustrated Lewis pairs bearing either a Lewis acidic group, a Lewis basic group or simultaneously both groups. We first accessed a new series of enantiopure biphenylphosphines that can find applications as Lewis base (including the field of frustrated Lewis pairs), as nucleophilic organocatalyst or as ligand in organometallic catalysis. Then, various methods were (re)developed to access chiral biphenyl-based Lewis acids: firstly, the functionalization of biphenyltrifluoroborate salts as chiral and enantiopure borane precursors and secondly the use of electrophilic silanes. The whole information and methodologies developed herein may be applied to the synthesis of new ambiphilic compounds as new atropo-frustrated Lewis pairs.

La plateforme ferrocène est fréquemment utilisée en chimie de coordination et en catalyse pour son excellente résistance aux conditions de réaction poussées. Le squelette ferrocène permet de maîtriser l’agencement de plusieurs groupes fonctionnels d’intérêt. Des ansa-ferrocènes et des ferrocènes à conformation contrainte, permettant par leur structure de contrôler une proximité des groupes fonctionnels, ont été décrits.La première partie de cette thèse traite de la synthèse de cyclopentadiényles borylés disubstitués et de leur réaction d’assemblage pour la formation de métallocènes borylés à conformation contrainte. Des analyses par RMN et des calculs par DFT ont permis de mettre en évidence la diastéréosélectivité inédite de la synthèse.À partir de cette approche, la deuxième partie traite de l’agencement de fonctions acides/bases de Lewis sur une plateforme ferrocénique à conformation contrainte. La synthèse de cyclopentadiényles (P/B) trisubstitués a été initiée. La synthèse de ligands ambiphiles (P/B) par assemblage de cyclopentadiénures et l’influence des tertio-butyles sur leur conformation ont été explorées. Une nouvelle forme de couplage de spin à trois centres sans liaison covalente, impliquant la lacune du bore dans la transmission de spin 31P31P, a été observée en RMN pour un P,P,B-ferrocène très original.La troisième partie traite de la synthèse de ferrocènes (P/B) et (N/B) à conformation contrainte. La voie de synthèse alternative et diastéréosélective proposée s’est révélée efficace alors que le rôle des tertio butyles dans le contrôle conformationnel a été démontré. L’étude de leur réactivité de type paire frustrée de Lewis a été initiée avec le CO2. / Ferrocene platforms are useful in coordination chemistry and catalysis thanks to their robustness and versatile functionalization. Ferrocene backbone allows the implantation of several key functional groups in a restricted space, inducing close proximity and potential polyfunctional cooperation (see for instance ferrocenyl polyphosphine chemistry). Ansa ferrocene and ferrocene bearing conformational control inducing groups maximizing the proximity of key groups have been widely reported.The first part of this thesis focuses on the synthesis of new borylated cyclopentadienyl, and their use in formation of borylated metallocenes bearing conformational constraints. NMR analysis and DFT calculation exhibits the diastereoselectivity of assembly reaction.The second part deals with the arrangement of several Lewis acids and bases on a constraint ferrocene platform. Synthesis of trisubstituted cyclopentadienyl (P/B) has been initiated. Synthesis of ambiphilic ligands (P/B) by assembly reaction of cyclopentadienides and the influence of tert-butyl groups on their conformation have been explored. A new 31P31P spin coupling transmitted “through-space (nonbonded spin-spin coupling transmission) involving for the first time an empty orbital has been observed.The third part describes the synthesis of heteroannular (P/B) and (N/B) ferrocene directly from ferrocene functionalization. An efficient and diastereoselective synthesis has been developed and the influence of tert-butyl groups on the conformational control has been highlighted in both solid and solution state. Studies of the frustrated Lewis pair reactivity of these new ambiphilic ligands have been initiated by addition of CO2.

Boiling is used in a wide variety of industries, including electronics cooling, distillation, and power generation. Fundamental studies on the boiling process are needed for effective implementation. Key performance characteristics of boiling are the heat transfer coefficient, which determines the amount of heat flux that can be dissipated for a given superheat, and critical heat flux(CHF), the failure point that occurs when vapor blankets the surface. The wettability of a surface is one of the key parameters that affects boiling behavior. Wetting surfaces(e.g., hydrophilic surfaces), typically characterized by a static contact angle below 90°,have better critical heat flux due to effective rewetting, but compromised heat transfer coefficients due to increased waiting times between nucleation of each bubble. Meanwhile, nonwetting surfaces (e.g., hydrophobic surfaces), characterized by static contact angles greater than 90°, have better heat transfer coefficients due to improved nucleation characteristic, but reach critical heat flux early due to surface dry out. However, recent studies have shown that the static contact angle alone offers and incomplete, and sometimes inaccurate, description of this behavior, which is instead governed entirely by the dynamic wettability. Specifically, the receding contact angle impacts the size and contact area of bubbles forming on a surface during boiling, while the advancing contact angle determines how the bubble departs. With this more complete set of wettability descriptors, three characteristic wetting regimes define the boiling behavior: hygrophilic surfaces having advancing and receding contact angles both under 90°; hygrophobic surfaces having both these dynamic contact angles over 90°;and ambiphilic surfaces having a receding contact angle less than 90°, but an advancing contact angle greater than 90°.The goal of this thesis is to experimentally characterize and compare the behavior of boiling surfaces in each of these regimes, observe the contact line behavior, and explain the mechanisms for their differences in performance.