Heterogeneous Catalysts for the One-Pot Synthesis of Chemicals and Fine Chemicals

[EN] It is apparent that intensi¿cation in chemical and most
\nspeci¿cally in catalytic processes is of growing in interest
\namong researchers. This is not only because of the potential
\neconomical impact if translated into industrial application,
\nTable 24. One-Pot r,r-Dialkylation of Nitriles using Metal/HTsa
\naReaction conditions: Method A: (i) nitrile (1 mmol) carbonyl compounds (1 mmol), Pd/HT (0.1 g; Pd 0.01 mmol), toluene (3 mL), 2 h, 80 °C,
\nAr. After completion of the aldol reaction, the reaction mixture was further treated at 60 °C for 1 h under H2 (1 atm). (ii) Ole¿n (1.5 mmol), 5 h,
\n70 °C, Ar. Method B: (i) nitrile (1 mmol), alcohol (2 mL), Ru/HT (0.15 g; 0.0075 mmol), 180 °C, 20 h, Ar. (ii) Ole¿n (3 mmol), DMSO (2 mL),
\n150 °C, 1 h, Ar. bOverall yield based on nitrile. cAt 110 °C, 12 h for Michael addition. dA solution of methyl vinyl ketone (1.5 mmol) in toluene
\n(2 mL) was slowly added over 6 h and further reacted for 4 h. eDMF (3 mL) was used as solvent. fDMF (3 mL) was used as solvent for Michael
\naddition. gDetermined by GC by an internal standart.
\nScheme 155. Sequential Acetal Hydrolysis Followed by
\nKnoevenagel Condensation and Subsequent Hydrogenation
\nScheme 156. Sequential Acetal Hydrolysis Followed by
\nAldol Type Condensations
\nHeterogeneous Catalysts for One-Pot Synthesis Chemical Reviews, 2011, Vol. 111, No. 2 1127but also because it is challenging and attractive to achieve
\nthe molecular design of a catalyst that allows cascade type
\nreactions to be performed.