Name: the synthesis, characterization and reactivity of a series of ruthenium n-triphosph complexes
Uploaded: 2015-04-10T14:00:00
Description: Watch this Scientific Journal Video about The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes at JoVE.com

AP is grateful to Imperial College London for a PhD studentship via the Frankland Chair endowment. Johnson Matthey plc are also thanked for the loan of the precious metal salts used in this work.

Note: Carry out all syntheses in a fume hood, and only after appropriate safety issues have been identified and measures taken to protect against them. Personal protective equipment include a lab coat, gloves and safety goggles and should be worn at all times.
1. Synthesis of N,N,N-tris(diphenylphosphinomethylene)amine, N(CH2PPh2)3 (N-triphosPh) (1)
<ol>
	<li>To a 200 ml oven dried Schlenk flask add diphenyl(hydroxymethylene)phosphonium chloride1...

<ol>
	<li>Bruneau, C., Dixneuf, P. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Ruthenium Catalysis and Fine Chemicals. , (2004).</li><li>Naota, T., Takaya, H., Murahashi, S. -. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ruthenium-Catalyzed+Reactions+for+Organic+Synthesis.">Ruthenium-Catalyzed Reactions for Organic Synthesis.</a> Chem. Rev. 98 (7), 2599-2660 (1998).</li><li>Arockaim, P. B., Bruneau, C., Dixneuf, P. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ruthenium(II)-Catalyzed+C-H+Bond+Activation+and+Functionalization.">Ruthenium(II)-Catalyzed C-H Bond Activation and Functionalization.</a> Chem. Rev. 112 (11), 5879-5918 (2012).</li><li>Trost, B. M., Toste, F. D., Pinkerton, A. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Non-metathesis+ruthenium-catalyzed+C-C+bond+formation.">Non-metathesis ruthenium-catalyzed C-C bond formation.</a> Chem. Rev. 101 (7), 2067-2096 (2001).</li><li>Vougioukalakis, G. C., Grubbs, R. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ruthenium-Based+Heterocyclic+Carbene-Coordinated+Olefin+Metathesis+Catalysis.">Ruthenium-Based Heterocyclic Carbene-Coordinated Olefin Metathesis Catalysis.</a> Chem. Rev. 110 (3), 1746-1787 (2010).</li><li>Lozano-Vila, A. M., Monsaert, S., Bajek, A., Verpoort, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ruthenium-based+olefin+metathesis+catalysts+derived+from+alkynes.">Ruthenium-based olefin metathesis catalysts derived from alkynes.</a> Chem. Rev. 110 (8), 4865-4909 (2010).</li><li>Samojlowicz, C., Bieniek, M., Grela, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ruthenium-based+olefin+metathesis+catalysts+bearing+N-heterocyclic+carbene+ligands.">Ruthenium-based olefin metathesis catalysts bearing N-heterocyclic carbene ligands.</a> Chem. Rev. 109 (8), 3708-3742 (2009).</li><li>Alcaide, B., Almedros, P., Luna, A. G. r. u. b. b. s. &. #. 8. 2. 1. 7. ;. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ruthenium-Carbenes+Beyond+the+Metathesis+Reaction:+Less+Conventional+Non-Metathetic+Utility.">Ruthenium-Carbenes Beyond the Metathesis Reaction: Less Conventional Non-Metathetic Utility.</a> Chem. Rev. 109 (8), 3817-3858 (2009).</li><li>Conley, B. L., Pennington-Boggio, M. K., Boz, E., Discovery Williams, T. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Applications,+and+Catalytic+Mechanisms+of+Shvo&#8217;s+Catalyst.">Applications, and Catalytic Mechanisms of Shvo&#8217;s Catalyst.</a> Chem. Rev. 110 (4), 2294-2312 (2010).</li><li>Miller, P. W., White, A. J. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+preparation+of+multimetallic+complexes+using+sterically+bulky+N-centered+tipodal+dialkyl+phosphine+ligands.">The preparation of multimetallic complexes using sterically bulky N-centered tipodal dialkyl phosphine ligands.</a> J. Organomet. Chem. 695 (8), 1138-1145 (2010).</li><li>Hanton, M. J., Tin, S., Boardman, B. J., Miller, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ruthenium-catalysed+hydrogenation+of+esters+using+tripodal+phosphine+ligands.">Ruthenium-catalysed hydrogenation of esters using tripodal phosphine ligands.</a> J. Mol. Catal. A. 346 (1-2), 70-78 (2012).</li><li>Phanopoulos, A., Brown, N. J., White, A. J. P., Long, N. J., Miller, P. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthesis,+Characterization,+and+Reactivity+of+Ruthenium+Hydride+Complexes+of+N-Centered+Triphosphine+Ligands.">Synthesis, Characterization, and Reactivity of Ruthenium Hydride Complexes of N-Centered Triphosphine Ligands.</a> Inorg. Chem. 53 (7), 3742-3752 (2014).</li><li>Jin, G. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=N.N.N-tris(phosphinomethylen)amine+N.N.N&#8217;-tris(phosphinomethylene)hydrazine+N.N.N&#8217;.N&#8217;-tetra(phosphinomethylene)hydrazine.">N.N.N-tris(phosphinomethylen)amine N.N.N&#8217;-tris(phosphinomethylene)hydrazine N.N.N&#8217;.N&#8217;-tetra(phosphinomethylene)hydrazine.</a> Tetrahedron Lett. 22 (12), 1105-1108 (1981).</li><li>Walter, O., Huttner, G., Kern, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preparation+and+Characterisation+of+N(CH2PPh2)3.+N(CH2PPh2)3Mo(CO)3+and+[HN(CH2PPh2)3Mo(CO)3]BF4.">Preparation and Characterisation of N(CH2PPh2)3. N(CH2PPh2)3Mo(CO)3 and [HN(CH2PPh2)3Mo(CO)3]BF4.</a> Z. Naturforsch. 51b, 922-928 (1996).</li><li>Fillol, J. L., Kruckenberg, A., Scherl, P., Wadepohl, H., Gade, L. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stitching+Phospholanes+Together+Piece+by+Piece:+New+Modular+Di-+and+Tridentate+Stereodirecting+Ligands.">Stitching Phospholanes Together Piece by Piece: New Modular Di- and Tridentate Stereodirecting Ligands.</a> Chem. Eur. J. 17 (50), 14047-14062 (2011).</li><li>Rodr&#237;guez, L. -. I., Roth, T., Fillol, J. L., Wadepohl, H., Gade, L. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+More+Gold&#8211;The+More+Enantioselective:+Cyclohydroaminations+of+&#947;-Allenyl+Sulfonamides+with+Mono+Bis,+and+Trisphospholane+Gold(I)+Catalysts.">The More Gold&#8211;The More Enantioselective: Cyclohydroaminations of &#947;-Allenyl Sulfonamides with Mono Bis, and Trisphospholane Gold(I) Catalysts.</a> Chem. Eur. J. 18 (12), 3721-3728 (2012).</li><li>Scherl, P., Kruckenberg, A., Mader, S., Wadepohl, H., Gade, L. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ruthenium+&#951;4-Trimethylenemethane+Complexes+Containing+Tripodal+Phosphanomethylamine+Ligands.">Ruthenium &#951;4-Trimethylenemethane Complexes Containing Tripodal Phosphanomethylamine Ligands.</a> Organometallics. 31 (19), 7024-7027 (2012).</li><li>Scherl, P., Wadepohl, H., Gade, L. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hydrogenation+and+Silylation+of+a+Double-Cyclometalated+Ruthenium+Complex:+Structures+and+Dynamic+Behavior+of+Hydrido+and+Hydridosilicate+Ruthenium+Complexes.">Hydrogenation and Silylation of a Double-Cyclometalated Ruthenium Complex: Structures and Dynamic Behavior of Hydrido and Hydridosilicate Ruthenium Complexes.</a> Organometallics. 32 (15), 4409-4415 (2013).</li><li>Geilen, F. M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Selective+and+Flexible+Transformation+of+Biomass-Derived+Platform+Chemicals+by+a+Multifunctional+Catalytic+System.">Selective and Flexible Transformation of Biomass-Derived Platform Chemicals by a Multifunctional Catalytic System.</a> Angew. Chem. Int. Ed. 49 (32), 5510-5514 (2010).</li><li>Geilen, F. M. A., Engendahl, B., H&#246;lscher, M., Klankermayer, J., Leitner, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Selective+Homogeneous+Hydrogenation+of+Biogenic+Carboxylic+Acids+with+[Ru(TriPhos)H]+:+A+Mechanistic+Study.">Selective Homogeneous Hydrogenation of Biogenic Carboxylic Acids with [Ru(TriPhos)H]+: A Mechanistic Study.</a> J. Am. Chem. Soc. 133 (36), 14349-14358 (2011).</li><li>Van Engelen, M. C., Teunissen, H. T., de Vries, J. G., Elsevier, C. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Suitable+ligands+for+homogeneous+ruthenium-catalyzed+hydrogenolysis+of+esters.">Suitable ligands for homogeneous ruthenium-catalyzed hydrogenolysis of esters.</a> J. Mol. Catal. A. 206 (1-2), 185-192 (2003).</li><li>Wesselbaum, S., vom Stein, T., Klankermayer, J., Leitner, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hydrogenation+of+Carbon+Dioxide+to+Methanol+by+Using+a+Homogeneous+Ruthenium&#8211;Phosphine+Catalyst.">Hydrogenation of Carbon Dioxide to Methanol by Using a Homogeneous Ruthenium&#8211;Phosphine Catalyst.</a> Angew. Chem. Int. Ed. 51 (30), 7499-7502 (2012).</li><li>Fillol, J. L., Kruckenberg, A., Scherl, P., Wadepohl, H., Gade, L. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stitching+Phospholanes+Together+Piece+by+Piece:+New+Modular+Di-+and+Tridentate+Stereodirecting+Ligands.">Stitching Phospholanes Together Piece by Piece: New Modular Di- and Tridentate Stereodirecting Ligands.</a> Chem. Eur. J. 17 (50), 14047-14062 (2011).</li><li>Rodr&#237;guez, L. -. I., Roth, T., Fillol, J. L., Wadepohl, H., Gade, L. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+More+Gold&#8211;The+More+Enantioselective:+Cyclohydroaminations+of+&#947;-Allenyl+Sulfonamides+with+Mono+Bis-,+and+Trisphospholane+Gold(I)+Catalysts.">The More Gold&#8211;The More Enantioselective: Cyclohydroaminations of &#947;-Allenyl Sulfonamides with Mono Bis-, and Trisphospholane Gold(I) Catalysts.</a> Chem. Eur. J. 18 (12), 3721-3728 (2012).</li><li>Scherl, P., Wadepohl, H., Gade, L. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hydrogenation+and+Silylation+of+a+Double-Cyclometalated+Ruthenium+Complex:+Structures+and+Dynamic+Behavior+of+Hydrido+and+Hydridosilicate+Ruthenium+Complexes.">Hydrogenation and Silylation of a Double-Cyclometalated Ruthenium Complex: Structures and Dynamic Behavior of Hydrido and Hydridosilicate Ruthenium Complexes.</a> Organometallics. 32 (15), 4409-4415 (2013).</li><li>Bennett, B. K., Richmond, T. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+Inexpensive,+Disposable+Cannula+Filtration+Device.">An Inexpensive, Disposable Cannula Filtration Device.</a> J. Chem. Educ. 75 (8), 1034 (1998).</li><li>Judd, C. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Proton+NMR+Basics.">Proton NMR Basics.</a> J. Chem. Educ. 72 (8), 706 (1995).</li><li>Rhodes, L. F., Venanzi, L. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ruthenium(II)-Assisted+Borohydride+Reduction+of+Acetonitrile.">Ruthenium(II)-Assisted Borohydride Reduction of Acetonitrile.</a> Inorg. Chem. 26 (16), 2692-2695 (1987).</li><li>Bakhmutov, V. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In-depth+NMR+and+IR+study+of+the+proton+transfer+equilibrium+between+[{MeC(CH2PPh2)3}Ru(CO)H2]+and+hexafluoroisopropanol.">In-depth NMR and IR study of the proton transfer equilibrium between [{MeC(CH2PPh2)3}Ru(CO)H2] and hexafluoroisopropanol.</a> Can. J. Chem. 79, 479-489 (2001).</li></ol>

Herein we have described efficient synthetic procedures for the synthesis of a tridentate phosphine ligand and a series of ruthenium complexes. The N-triphosPh ligand (1) can be easily prepared in high yield with a minimalistic work-up procedure. This phosphorus based Mannich reaction used to synthesize these types of ligands is quite general and can be used for other ligand derivatives with differing R-groups on the P-atoms.10-12,15-18 Additionally, this synthetic methodol...

Ruthenium phosphine based complexes are some of the most widely studied and chemically versatile molecular catalysts.1-9 Typically, such ruthenium catalysts contain either mono- or bi-dentate ligands that dictate the electronics, sterics, geometry and solubility of the complex, and which profoundly impact on catalytic activity. Multidentate phosphine systems have been less widely studied for catalysis, as they are known to impart greater stability on the metal center owing to the greater chelate effect of multiple phosphorus donors on the metal center. Such stabilization can be undesirable for catalysis, however, under harsher reaction conditions (higher temperatures and pressures) the complex stabilizing properties of such ligands can be advantageous in ensuring catalyst integrity. One such multidentate phosphine ligand system that we10-12 and others13-18 have investigated for imparting complex stability and facial coordination geometries is the so-called N-triphos ligand series where three phosphine arms are attached to an apical bridging nitrogen atom forming a potentially tridentate ligand. One of the key features to these particular ligands is the facile way that they can be synthesized via a phosphorus based Mannich reaction from readily available secondary phosphines (Figure 1), hence phosphines with a variety of R-groups can be prepared usually in high yields and with minimal work-up. The overall goal of this methodology is to present a facile route by which ruthenium dihydride complexes featuring N-triphos ligands can be accessed for subsequent catalytic applications. Recently, Ru-triphos based complexes have attracted attention as catalysts for the hydrogenation reactions of biomass derived products, such as levulinic acid,19,20 bio-esters11,21 and carbon dioxide22 to higher value chemicals. It would be advantageous to expand the scope of Ru-triphos derivatives that are either as, or more active than the systems already reported, especially if they are synthetically easier to access, such as the N-triphos ligand. The most studied carbon-centered analogue typically suffers from low yielding synthesis and involves highly air-sensitive metal phosphide reagents, unlike the N-triphos ligand, which is more adaptable and easier to prepare.10-18
N-triphos ligands remain relatively under-investigated, with only molybdenum, tungsten, ruthenium, rhodium and gold complexes having been reported from nine publications. This is in stark contrast to the boron- and carbon-centered analogues, for which there are around 50 and 900 articles, respectively, with a great number of unique compounds. Nonetheless, N-triphos containing complexes have found application in the asymmetric catalytic hydrogenation of pro-chiral olefins23 as well as asymmetric cyclohydroamination of N-protected &#947;-allenyl sulfonamides.24 Additionally, a ruthenium complex coordinated by a bulky N-triphos ligand featuring phospholane coordinating moieties was found to activate silanes, a key step in the development of organosilicon chemistry.25
As part of the ongoing research program in catalysis, we sought to prepare a range of ruthenium N-triphosPh precatalysts and to investigate their stoichiometric reactions and catalytic potential. Despite molybdenum complexes of N-triphosPh having first been reported over 25 years ago, their application, catalytic or otherwise has not been investigated. This work demonstrates the applicability of the N-triphos scaffold, which despite being generally underdeveloped, possess many desirable features such as complex stability. Herein we report the synthetic route and characterization of to a series of ruthenium N-triphosPh complexes that may find application in catalytic hydrogenation reactions.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>Methanol</td>
			<td rowspan="5">&#8211;</td>
			<td rowspan="5">&#8211;</td>
			<td rowspan="5">Obtained from in-house solvent purification system: Innovative Technology, inc &#34;pure solv&#34; drying tower. Stored in ampules over activated molecular sieves under nitrogen.</td>
		</tr>
		<tr>
			<td>Toluene</td>
		</tr>
		<tr>
			<td>Diethyl Ether</td>
		</tr>
		<tr>
			<td>Tetrahydrofuran (THF)</td>
		</tr>
		<tr>
			<td>Acetonitrile</td>
		</tr>
		<tr>
			<td>d6-Acetone</td>
			<td>VWR</td>
			<td>VWRC87152.0011</td>
			<td>Store in fridge</td>
		</tr>
		<tr>
			<td>Triethylamine</td>
			<td>Sigma-Aldrich</td>
			<td>TO886-1L</td>
			<td>Distilled and stored over activated molecular sieves under N2</td>
		</tr>
		<tr>
			<td>2M Ammonia solution in methanol</td>
			<td>Sigma-Aldrich</td>
			<td>341428-100ML</td>
			<td>Solution comes in a &#34;Sure-Seal&#34; bottle</td>
		</tr>
		<tr>
			<td>NH4PF6</td>
			<td>Sigma-Aldrich</td>
			<td>216593-5G</td>
			<td>Store in desiccator</td>
		</tr>
		<tr>
			<td>Levulinic Acid</td>
			<td>Acros Organics</td>
			<td>125142500</td>
			<td>Solid but melts close to room temperature</td>
		</tr>
		<tr>
			<td>3 &#197; Molecular sieves</td>
			<td>Alfa Aesar</td>
			<td>LO5359</td>
			<td>Activate by heating over night under vacuum</td>
		</tr>
		<tr>
			<td>Schlenk flasks</td>
			<td>GPE</td>
			<td>Custom design</td>
			<td>&#8211;</td>
		</tr>
		<tr>
			<td>Dual-manifold Schlenk line</td>
			<td>GPE</td>
			<td>Custom design</td>
			<td>Dual-manifold of i) N2 that has been passed through a silica drying column and ii) vacuum.</td>
		</tr>
		<tr>
			<td>Rotary vacuum pump</td>
			<td>Edwards</td>
			<td>RV3 A652-01-903</td>
			<td>&#8211;</td>
		</tr>
		<tr>
			<td>100 ml Autoclave Engineer&#39;s high pressure reactor</td>
			<td>Autoclave Engineer</td>
			<td>Custon design</td>
			<td>&#8211;</td>
		</tr>
		<tr>
			<td>Vortex Stirrer</td>
			<td>VWR</td>
			<td>444-1378</td>
			<td>&#8211;</td>
		</tr>
	</tbody>
</table>

the synthesis, characterization and reactivity of a series of ruthenium n-triphosph complexes

Herein we report the synthesis of a tridentate phosphine ligand N(CH2PPh2)3 (N-triphosPh) (1) via a phosphorus based Mannich reaction of the hydroxylmethylene phosphine precursor with ammonia in methanol under a nitrogen atmosphere. The N-triphosPh ligand precipitates from the solution after approximately 1 hr of reflux and can be isolated analytically pure via simple cannula filtration procedure under nitrogen. Reaction of the N-triphosPh ligand with [Ru3(CO)12] under reflux affords a deep red solution that show evolution of CO gas on ligand complexation. Orange crystals of the complex [Ru(CO)2{N(CH2PPh2)3}-&#954;3P] (2) were isolated on cooling to RT. The 31P{1H} NMR spectrum showed a characteristic single peak at lower frequency compared to the free ligand. Reaction of a toluene solution of complex 2 with oxygen resulted in the instantaneous precipitation of the carbonate complex [Ru(CO3)(CO){N(CH2PPh2)3}-&#954;3P] (3) as an air stable orange solid. Subsequent hydrogenation of 3 under 15 bar of hydrogen in a high-pressure reactor gave the dihydride complex [RuH2(CO){N(CH2PPh2)3}-&#954;3P] (4), which was fully characterized by X-ray crystallography and NMR spectroscopy. Complexes 3 and 4 are potentially useful catalyst precursors for a range of hydrogenation reactions, including biomass-derived products such as levulinic acid (LA). Complex 4 was found to cleanly react with LA in the presence of the proton source additive NH4PF6 to give [Ru(CO){N(CH2PPh2)3}-&#954;3P{CH3CO(CH2)2CO2H}-&#954;2O](PF6) (6).

The N-triphosPh ligand (1) and the ruthenium complex series: Ru(CO)2{N(CH2PPh2)3}-&#954;3P] (2), [Ru(CO3)(CO){N(CH2PPh2)3}-&#954;3P] (3) and [Ru(H)2(CO){N(CH2PPh2)3}-&#954;3P] (4) were characterized via 1H, 13C{1H...

Watch this Scientific Journal Video about The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes at JoVE.com

The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes

Ruthenium phosphine complexes are widely used for homogeneous catalytic reactions such as hydrogenations. The synthesis of a series of novel tridentate ruthenium complexes bearing the N-triphos ligand N(CH2PPh2)3 is reported. Additionally, the stoichiometric reaction of a dihydride Ru&#8211;N-triphos complex with levulinic acid is described.

The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes

Herein we report the synthesis of a tridentate phosphine ligand N(CH2PPh2)3 (N-triphosPh) (1) via a phosphorus based Mannich reaction of the ...

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Synthesis and Characterization of Supramolecular Colloids

Control over colloidal assembly is of utmost importance for the development of functional colloidal materials with tailored structural and mechanical ...

Synthesis of Protein Bioconjugates via Cysteine-maleimide Chemistry

Synthesis of Protein Bioconjugates via Cysteine-maleimide Chemistry

The chemical linking or bioconjugation of proteins to fluorescent dyes, drugs, polymers and other proteins has a broad range of applications, such as the ...

Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level

We demonstrate a method for the synthesis of cyclic polymers and a protocol for characterizing their diffusive motion in a melt state at the single ...

Combining Solid-state and Solution-based Techniques: Synthesis and Reactivity of Chalcogenidoplumbates(II or IV)

Combining Solid-state and Solution-based Techniques: Synthesis and Reactivity of ChalcogenidoplumbatesII or IV

The phases of &#34;PbCh2&#34; (Ch = Se, Te) are obtained from solid-state syntheses (i.e., by the fusion of the elements under inert conditions in silica ...