91192-25-5Relevant academic research and scientific papers
Pendant Alkoxy Groups on N-Aryl Substitutions Drive the Efficiency of Imidazolylidene Catalysts for Homoenolate Annulation from Enal and Aldehyde
Kyan, Ryuji,Mase, Nobuyuki,Narumi, Tetsuo,Sato, Kohei
, p. 19031 - 19036 (2020/08/25)
Hydrogen-transfer in the tetrahedral intermediate generated from an imidazolylidene catalyst and α,β-unsaturated aldehyde forms a conjugated Breslow intermediate. This is a critical step affecting the efficiency of the NHC-catalyzed γ-butyrolactone formation via homoenolate addition to aryl aldehydes. A novel type of imidazolylidene catalyst with pendant alkoxy groups on the ortho-N-aryl groups is described. Catalyst of this sort facilitates the formation of the conjugated Breslow intermediate. Studies of the rate constants for homoenolate annulation affording γ-butyrolactones, reveal that introduction of the oxygen atoms in the appropriate position of the N-aryl substituents can increase the efficiency of imidazolylidene catalysts. Structural and mechanistic studies revealed that pendant alkoxy groups can be located close to the proton of the tetrahedral intermediate, thereby facilitating the proton transfer.
PHENYLALKYL AND PYRIDYLALKYL PIPERAZINE DERIVATIVES
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Page 64, (2010/02/07)
This invention relates to compounds of the formula (1) wherein R1, R3, R4, X1, and X2 are defined as in the specification, pharmaceutical compositions containing them and their use in the treatment of central nervous system and other disorders.
One-Step Synthesis of 2- and 4-Nitrobenzyl Cyanides
Kalir, Asher,Mualem, Rivka
, p. 514 - 515 (2007/10/02)
2-Nitrobenzyl cyanide (2) and analogs were obtained in fair to good yields by reacting the corresponding bromides with sodium cyanide and hydrogen cyanide in dimethyl sulfoxide.Hydrogen cyanide could be generated in situ from an excess of sodium cyanide and trifluoroacetic acid.
