Triflate anion , hydrogenation with

If the anions of these acids are good leaving groups, elimination from their enol esters can be effected by the bases used for elimination of hydrogen halides. Enol triflates, on treatment with pyridine (Scheme 46), 2,6-di-r-butyl phenoxide (Scheme 47) or potassium r-butoxide (Scheme 48) yield the corresponding alkynes. 

The crystal structure of the hydrated scandium triflate has been determined. Nine water molecules surround the scandium ion and the triflate anions are hydrogen bonded to the water molecules.206 A structural analysis of anhydrous scandium triflate, using X-ray powder diffraction and IR spectroscopy, indicates that the triflate acts as a bidentate ligand with scandium in an octahedral environment.207... 

The solubility of the catalyst salt is improved by the use of 3,5-bis(trifluoromethyl)phenylborate or triflate anions. Unsaturated fatty acids can be reduced in the same way.173 Hydrogenations in sc carbon dioxide can be more selective than in the gas phase while using 35 times less catalyst.174 Cyclohexene was reduced with hydrogen and a polysilox-ane-supported palladium catalyst in in a continuous-flow reactor in 95-98% yields. Epoxides, oximes, nitriles, aldehydes, ketones, and nitro compounds can also be reduced. By varying the temperature, the products from the reduction of nitrobenzene can be selected from aniline, cyclo-hexylamine, dicyclohexylamine, and cyclohexane. In the... 

The X-ray structure of 58 reveals that the molecule is planar with the interatomic distances C(2)-N(3) and C(2)-N(7) suggesting double-bond character. The intermolecular distance between the heterocyclic cation and triflate anion N(3)-0 = 2.79 A (H(3)- -O = 1.88 A) suggests hydrogen-bond contact (Figure 1). 

Triflate anions are omitted for clarity.) Yb(OTf)3, (i )-(+)-BINOL and DBU form a complex with two hydrogen bonds, and the axial chirality of (/ )-(+)-BINOL is transferred via the hydrogen bonds to the amine parts. The additive would interact with the phenolic hydrogen of the imine, which is fixed by bidentate coordination to Yb(lll). Since the top face of the imine is shielded by the amine, the dienophiles approach from the bottom face to achieve high levels of selectivity. 

The SHB concept was expanded to chiral phosphine catalysts by de Rege et al., who reacted the trifluoromethanesulfonate (triflate) counter anion of the cationic complex [Rh(COD)((R,Rj-MeDuPhos)] with the surface hydroxyl groups of the silaceous mesoporous material MCM-41 [122]. The complex was loaded to a level of 1.03 wt% Rh. A decrease in support surface area and pore volume is consistent with the complex being located within the support pores. The counterion is very important in this process if the anion of the homogeneous catalyst precursor is altered to BArp no adsorption of the catalyst is observed. It is postulated that the mechanism of triflate binding is hydrogen bonding with the support, and that the... 

Fluoride anion can both react with silylaryl triflate to generate benzyne and act as a base to abstract the hydrogen on the amide nitrogen to afford an anion that can attack the benzyne. Intramolecular nucleophilic attack on the carbonyl carbon (or... 

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