This suggests addition of the metal complex to mesitylene causes downfield shifting of the signal for protons attached directly to the ring as they are unshielded from the backbonding of carbonyl groups. The reaction specifically takes place in the following manner: Scheme 1 This is compound of interest because it a metal-arene complex and can be considered to be an octahedral rather than tetrahedral complex. The IR spectrum of [1,3,5-C6H3 CH3 3]Mo CO 3 can be analyzed for peaks indicative of symmetrical and antisymmetrical carbonyl stretching, whose areas can be used to calculate the bond angle between the carbonyl groups attached the to metal. Experimental All syntheses were carried out in nitrogen and the reagents and solvents were purchased from commercial sources and used as received unless otherwise noted.
In this experiment, you will observe the reaction of a? This form of coordination is relatively common with olefins and metal atoms, the most famous being Mesitylene tricarbonylmolybdenum, cyclopentadiene 2Fe.
It is composed of two 5-membered rings situated directly above and below the metal center. It looks like an iron sandwich. The reaction of molybdenum hexacarbonyl and mesitylene is unstable with respect to air.
We will focus our efforts on the use of a Schlenk line in this laboratory.
A Schlenk line is a piece of equipment that is designed with the purpose of conducting experimental operations and techniques under an inert air environment. You will be shown how to use a Schlenk line during lab. Experimental Metal carbonyls can be very toxic and should be handled carefully and weighed in a hood.
Fortunately, we are working with Mo CO 6, which has a higher sublimation point. In addition, the reaction will produce a bit of CO g which, at high levels can be fatal. Since your reaction vessels will be vented into a hood, you will not need to be concerned about asphyxiation.
Week 1 — synthesis and Schlenk line techniques. Place a condenser on the r. Mo CO 6 will sublime and stick to the walls of the condenser. It can be washed back to the round bottom flask by the mesitylene if the condenser is not cooled by water — the temperature of the air around the condenser will be sufficient to condense the mesitylene.
Flush the solution with N2 from the Schlenk line for a couple of seconds then close the joints and boil the solution under a N2 atmosphere for 30 minutes.
Turn off the heat and let the solution cool. A yellow precipitate should appear.
Filter the precipitate over a medium frit and wash it with 5 mL of hexanes.Dec 23, · g of clean dry sand are placed in a 2ooo ml retort connected with a condenser.
g of acetone are added, and then a cooled mixture of g of concentrated sulfuric acid and g of water is run in, in a slow continuous stream, the retort being meantime cooled in cold water.
After 24 hours standing, the mixture is slowly distilled, directly or in steam. ChemicalBook ProvideMesitylene() 1 HNMRIR2,MS,IR3,IR1,1HNMR,Raman,ESR,13CNMR,Spectrum.
Sigma-Aldrich offers a number of Mesitylene products. View information & documentation regarding Mesitylene, including CAS, MSDS & more.
(1,3,5-C6H3(CH3)3)Mo(CO)3, Mesitylene Tricarbonylmolybdenum(0) I Place 1 g of Mo(CO)6 and 10 mL mesitylene in a small round bottom flask equipped with a stirbar. Place a condenser on the r. b. flask and a gas adapter on the top of the condenser.
(Mo(CO)6 will . Mar 17, · This is compound of interest because it a metal-arene complex and can be considered to be an octahedral rather than tetrahedral complex.
This is because the OC-Mo-CO bond angles are close to 90° instead of the expect ° for tetrahedrals. 1 In order to determine the structure of said substance from its 1 H NMR, the peaks must be compared to the same spectrum of mesitylene for .
Synthesis of (η , 3, 5-Methylbenzene)tricarbonylmolybdenum(0) Last Update: August 30, The procedure of Girolami et al. 1 is to be followed. An analysis of the compound’s IR spectrum as part of its characterization is required.
If time permits, you may attempt replacement of one, or more, of the carbonyl groups with a phosphine, PR 3.