1,1,3,3-Tetramethylguanidinium lactate

Another SILP catalyst used under batch conditions employed mesoporous MCM-41 as the solid support. The catalyst was derived from [Rh(CO)2(acac)] and TPPTS (1 5 mol ratio) in the desired IL. The excellent catalytic performance of this SILP catalyst in the hydroformylation of C6-C12 linear alkenes (TOF up to 500 h ) was determined by the large surface area and uniform mesopore structure of MCM-41 and was almost independent of the type of IL used [bmim][BF4], [bmim][PF6] and 1,1,3,3-tetramethylguanidinium lactate. 

Hydroformylation of 1-hexene has also later been performed using a MCM-41 supported Rh-TPPTS catalyst based on the ionic hquid 1,1,3,3-tetramethylguanidinium lactate (TMGL) [90]. Here the catalysts exhibited practically unchanged performance in twelve consecutive runs providing about 50% conversion and also low n/iso ratios of ca. 2.5. 

Moreover, the NPs prepared in ILs may be deposited on other supports. For example, Pt(0) and Rh(0) NPs prepared in 1,1,3,3-tetramethylguanidiniumtrifluo-roacetate or 1,1,3,3-tetramethylguanidinium lactate ILs, via reduction of their halide salts with glycol and with the aid of microwave heating, may be decorated onto carbon nanotubes in the presence of ILs [122],... 

ILs also allow tuning selectivity in consecutive reactions. Palladium nanoparticles (1-2 nm diameter) immobilized in 1,1,3,3-tetramethylguanidinium lactate (TMGL) supported on molecular sieves, for example, were used as catalyst of Type B for the solvent-free hydrogenation of alkenes and dienes at low temperatures (20-40 °C) [61]. Cyclohexadiene was converted faster than cyclohexene (TOP 65 and 20 mol molp min at 20 °C, respectively), which allowed the selective hydrogenation of cyclohexadiene to cyclohexene (Eq. (10.2)). Note that also the access of hydrogen and small alkenes to a metal surface below a layer of IL (Type C) does not seem to be restricted [55, 73]. 

Tetramethylguanidinium lactate ( TMGH][Lac]) (see Figure 21.3) was used by Wu and Zhu, et al. [5] in 2009 for SO2 removal. The IL was dispersed on silica particles via an incipient wetness technique and the resulting materials were carefully characterized. The intrusion volume, specific surface area, and porosity decreased with higher IL loading, while at the same time the apparent density and... 

An efficient protocol for the aza-Michael addition of aliphatic and aromatic amines to electron-deficient alkenes using 1,1,3,3-tetramethylguanidinium lactate as catalyst under solvent-free conditions has been established. ... 

Carriers other than silica have also been used for the preparation of SILP catalyst for the alkenes hydroformylation. Simple immobilized water-soluble TPPTS-Rh complex dissolved in 1,1,3,3-tetramethylguanidinium lactate ionic liquid on MCM-41 mesoporous silicas exhibited high performance and stability for the hydroformylation of 1-hexene, and the catalyst system could be reused many times without reducing the activity and selectivity. In these cases, considerable amounts of IL and Rh species were essentially located in the inner charmel of MCM-41. The SILP process performed using Si02 as the carrier presented much lower 1-hexene conversion as compared to the SILPC using MCM-41 under the same reaction conditions [47,48]. 

The Heck reaction of olefins with aryl halides proceeds successfully in the presence of palladium catalyst supported on TMG (1) modified molecular sieves without solvent. The TMG-Pd was found to be much more active and stable than the palladium catalyst without modification with TMG (1) [87]. An ionic liquid, tetramethylguanidinium lactate, was used as the TMG source. 

TMGL= 1,133-tetramethylguanidinium lactate BMPy = N-butyl-4-methylpyridinium BMI = l-ja-butyl-3-methylimidazolium A336 = Aliquat A336 based IL (trioctylmethylammonium) /IL = l- -butyl-3-(3-amidopropyl)imidazolium (TESP)MI = N -3-(3-triethoxysilylpropyl)-3-methylimidazolium ... 

Several research groups have reported ionic liquid-containing microanul-sions, but literature on the ionic liquid-in-SCF microemulsion is limited. It includes ionic liquids, 1,1,3,3-tetramethylguanidinium acetate, 1,1,3,3-telra-methylguanidinium lactate, and 1,1,3,3-tetramethylguanidinium trifluoroace-tate in SCCO2 with the aid of surfactant A-ethyl perfluorooctylsulfonamide [40]. 

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