Which catalyst is better for the Miyaura Borylation reaction out of PdCl2(dppf). CH2Cl2 and PdCl2(dppf).
I can propose that the solvent molecules lice DCM would not affect it strongly. However, if you need the solvate, try to crystallize the complex from DCM.
Efficiency depends upon substrates you are taking for reaction. Generally PdCl2(dppf).CH2Cl2 works good but PdCl2(dppf) can be use instead of former one.
Mr. Kumar,
[1] Iin benzene: mixt. of soln. of Pd-compound in benzene and soln. of ferrocene derivative in benzene, stirred (12 h, 20°C); filtration, washed with a little benzene, evapn. elem. anal. (Corain, B. et al. Inorganica Chimica Acta, 1989 , 157, 259 -266)
Accounting the competitiveness between the PdCl2(dppf) and PdCl2(dppf).CH2Cl2 complexes you can pay attention to [ref. 2].
[ref. 2] Tatsuo Ishiyama, Miki Murata, and Norio Miyaura , Palladium(0)-Catalyzed Cross-Coupling Reaction of Alkoxydiboron with Haloarenes: A Direct Procedure for Arylboronic Esters , J. Org. Chem. 1995,60, 7508-7510
As others have already indicated, the DCM of crystallization should not affect your reaction other than the change in molar mass and the calculation of the moles of catalyst.
Use Pd(COD)Cl2 in dichloromethane. Solvated CH2Cl2 will go away in solution.
Crystalize ur complex in DCM/Et2O. If possible try to crystalize ur complex in DMSO, also.
To a 1:1 (molar ratio) mixture of PdCl2 + Dppf, add dry acetonitrile and reflux for 4-5 h and your complex is ready. You can crystallize it by adding diethyl ether and cooling to zero oC. As an alternate, you can use Pd(COD)Cl2 in dichloromethane. Solvated CH2Cl2 will go away in solution and it has no role in any further reactions of the palladium complex. You have to be careful with CHCl3 as it is a source of HCl which can spoil your reaction. For the reaction you have mentioned, CH2Cl2 is harmless.
Although you could try to recrystallize your compound from DCM, I agree with the other colleagues that have indicated that no effect from the solvate on the borylation should be expected.
I have used those two and there is no difference, because DCM is just the solvent that gets trapped in the catalyst. Maybe you could say us what is your substrate?
Choose the PdCl2(dppf)-DCM complex if your substrate has an active lone pair that could interfere in the borylation or coupling reaction. For the reaction to occur, either PdCl2(dppf) is adequate.
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