Pd–benzothiazol-2-ylidene complex in ionic liquids: Efficient catalyst for carbon–carbon coupling reactions

Accelerated Heck reaction using ortho‐palladated complex in a nonaqueous ionic liquid with controlled microwave heating

“…[52] Indeed, the planar structures of [bmim] + cations, by binding tightly the halide ions, decrease their availability. [53] Weak interaction of the bromide anion with tetrabutylammonium cation in TBAB makes possible the reaction of bromide with the relatively unstable 14-electron complex L 2 Pd(0) that achieved palladacycle A. This reaction would lead to an anionic, more stable and catalytically active 16-electron complex [L 2 Pd(0)Br] − NR 4 + .…”

Palladium catalysed hydroxycarbonylation of 1-phenylethanol in molten salt media

“…This point is closely discussed in [42]. The bulky tetrahedral ammonium ion forces the halides anions away from the cation, thus making them more nucleophilic and available for the catalyst activity as compared with the planar [BMIM + ] [29,42].…”

Ionic liquids: a versatile medium for palladium-catalyzed reactions

“…ILs have made significant progress in recent years in the catalytic processes. [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] They are liquid salts in which the ions are poorly coordinated. ILs are not simply salts dissolved in liquid but they usually exist as liquid below 100 °C, or even at room temperature (room temperature ionic liquids; RTILs).…”

“…Pd-benzothiazol-2-ylidene complex (2) catalyzes efficiently the C-C coupling reactions of activated aryl halides with very high turnover number in the ionic liquid Bu 4 NBr as solvent (Scheme 10). 22 The Pdbenzothiazol-2-ylidene complex was known but it did not find any application as a catalyst for Heck reaction. This complex was modified by Calo et al 105 by reaction of 3-methylbenzothiazolium iodide with palladium acetate in THF and used for Heck reactions.…”

“…On the other hand, IL with planar structures and poor nucleophilic anions are not efficient in influencing the reactivity and stability of the catalyst. 22 The reaction of 2-methylprop-2-en-1-ol with a range of aryl halides under homogeneous and heterogeneous catalyst system in organic solvents and IL has been reported. 92 In particular, the formation of 3-(4-t-butylphenyl)-2-methylpropanal ( -Lilial) has been examined in detail (Scheme 11).…”