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Ionic liquid with both Lewis and Brønsted acid sites has been synthesized and its catalytic activities for Michael addition were carefully studied. The novel ionic liquid was stable to water and could be used in aqueous solution. The molar ratio of the Lewis and Brønsted acid sites could be adjusted to match different reactions. The results showed that the novel ionic liquid was very efficient for Michael addition with good to excellent yields within several min. Operational simplicity, high stability to water and air, small amount used, low cost of the catalyst used, high yields, chemoselectivity, applicability to large-scale reactions and reusability are the key features of this methodology, which indicated that this novel ionic liquid also holds great potential for environmentally friendly processes.

A novel route for the total synthesis of ε-carotene is described. The synthesis is based on a condensation between α-cyclocitral and diethyl [(2E)-3-methoxy-2-methylprop-2-en-1-yl]phosphonate to give a C 14 enol ether, hydrolysis of the C 14 -enol ether to a give a C 14 aldehyde, and a modified Wittig-Horner reaction of the C 15 phosphonate from the C 14 aldehyde and a C 10 triene dialdehyde to give ε-carotene. The synthetic steps are easily performed and are practical for largescale production.

Practical Synthesis of -Carotene. -The developed route is supposed to be useful for a large-scale preparation of the title compound. -(WU, C.; CAO, R.; SONG, X.; LV, C.; YE, W.; PI, S.; CHEN, C.; SHEN*, R.; Synthesis 47 (2015) 4, 481-484, http://dx.