- Synthesis method of trans-4-oxo-2-hexenal
-
The invention discloses a synthesis method of trans-4-oxo-2-hexenal. The synthesis method comprises the following steps: bromobutanone and triphenylphosphine are used as initial raw materials; in organic solvents, the compound is prepared by the following synthetic route. By adopting a brand-new synthesis route, the whole synthesis process is simple and convenient to operate, the reaction conditions of each reaction stage are mild and controllable, the safety is high, the equipment investment is low, the yield of each intermediate product is 90% or above, and the yield of the final product trans-4-oxo-2-hexenal is high and is improved by 30% or above compared with the prior art; according to the method, the raw materials which are low in cost and easy to obtain are adopted, and the methodis suitable for industrial production and has important significance in realizing the release production of the sex pheromones of the apolygus lucorum.
- -
-
Paragraph 0040-0042
(2020/10/20)
-
- Titania-promoted carboxylic acid alkylations of alkenes and cascade addition-cyclizations
-
Photochemical reactions employing TiO2 and carboxylic acids under dry anaerobic conditions led to several types of C-C bond-forming processes with electron-deficient alkenes. The efficiency of alkylation varied appreciably with substituents in the carboxylic acids. The reactions of aryloxyacetic acids with maleimides resulted in a cascade process in which a pyrrolochromene derivative accompanied the alkylated succinimide. The selectivity for one or other of these products could be tuned to some extent by employing the photoredox catalyst under different conditions. Aryloxyacetic acids adapted for intramolecular ring closures by inclusion of 2-alkenyl, 2-aryl, or 2-oximinyl functionality reacted rather poorly. Profiles of reactant consumption and product formation for these systems were obtained by an in situ NMR monitoring technique. An array of different catalyst forms were tested for efficiency and ease of use. The proposed mechanism, involving hole capture at the TiO2 surface by the carboxylates followed by CO2 loss, was supported by EPR spectroscopic evidence of the intermediates. Deuterium labeling indicated that the titania likely donates protons from surface hydroxyl groups as well as supplying electrons and holes, thus acting as both a catalyst and a reaction partner.
- Manley, David W.,McBurney, Roy T.,Miller, Phillip,Walton, John C.,Mills, Andrew,O'Rourke, Christopher
-
p. 1386 - 1398
(2014/03/21)
-