Hydrothermal liquefaction of corn straw with different catalytic systems and temperatures were investigated in this study. Results showed dual catalytic system can effectively promote the degradation of corn straw at low temperature. With increase of temperature, aqueous phase increased and straw residue decreased for all catalytic systems. The heavy bio-oil yield increased with the increasing of temperature for single catalytic system, while the trend was opposite for dual catalytic system. In single catalytic system, ZnFe 2 O 4 was more suitable for preparation of heavy bio-oil, and the maximum yield reached 34.02 wt% at 180 °C. The proportion of monophenyl compounds in heavy bio-oil for dual catalytic system reached the maximum of 84% at 220 °C with ZnFe 2 O 4 . At 180 °C, the contents of Benzofuran,2,3-dihydro and 2-Methoxy-4-vinylphenol reached the maximum of 31.42% and 17.64% in CoFe 2 O 4 catalyst system, and the maximum yield of Vanillin was 10.82% with ZnFe 2 O 4 .
The first sequentially combined inorganic base promoted N-addition/[2,3]-sigmatropic rearrangement reaction of α-alkylidene pyrazolinones and propargyl sulfonium salts has been reported to construct homoallyl sulfur-containing pyrazolones with moderate to excellent yields. α-Alkylidene pyrazolinones function as N-nucleophilic agents distinguished from the reported C-addition reactions. Propargyl sulfonium salts were first involved in the [2,3]-sigmatropic rearrangement protocol differentiated from the well-established annulation reactions. The excellent regioselectivity, the broad scope of substrates, gram-scale synthesis and convenient transformation embody the synthetic superiority of this cascade process.