Enantioselective α-Hydroxylation by Modified Salen-Zirconium(IV)-Catalyzed Oxidation of β-Keto Esters.

Title Enantioselective α-Hydroxylation by Modified Salen-Zirconium(IV)-Catalyzed Oxidation of β-Keto Esters.
Authors Yang, F.; Zhao, J.; Tang, X.; Zhou, G.; Song, W.; Meng, Q.
Journal Org Lett
DOI 10.1021/acs.orglett.6b03554
Abstract

The highly enantioselective α-hydroxylation of β-keto esters using cumene hydroperoxide (CHP) as the oxidant was realized by a chiral (1S,2S)-cyclohexanediamine backbone salen-zirconium(IV) complex as the catalyst. A variety of corresponding chiral α-hydroxy β-keto esters were obtained in excellent yields (up to 99%) and enantioselectivities (up to 98% ee). The zirconium-catalyzed enantioselective α-hydroxylation of β-keto esters was scalable, and the zirconium catalyst was recyclable. The reaction can be performed in gram scale, and corresponding chiral products were acquired in 95% yield and 99% ee.

Citation Yang, F.; Zhao, J.; Tang, X.; Zhou, G.; Song, W.; Meng, Q..Enantioselective α-Hydroxylation by Modified Salen-Zirconium(IV)-Catalyzed Oxidation of β-Keto Esters..

Related Elements

Zirconium

40 Zr 91.224000000 Zirconium

See more Zirconium products. Zirconium (atomic symbol: Zr, atomic number: 40) is a Block D, Group 4, Period 5 element with an atomic weight of 91.224. Zirconium Bohr ModelThe number of electrons in each of Zirconium's shells is 2, 8, 18, 10, 2 and its electron configuration is [Kr]4d2 5s2. The zirconium atom has a radius of 160 pm and a Van der Waals radius of 186 pm. Zirconium was discovered by Martin Heinrich Klaproth in 1789 and first isolated by Jöns Jakob Berzelius in 1824. In its elemental form, zirconium has a silvery white appearance that is similar to titanium. Zirconium's principal mineral is zircon (zirconium silicate). Elemental ZirconiumZirconium is commercially produced as a byproduct of titanium and tin mining and has many applications as a opacifier and a refractory material. It is not found in nature as a free element. The name of zirconium comes from the mineral zircon, the most important source of zirconium, and from the Persian wordzargun, meaning gold-like.

Publish your research on the American Elements website