Silicon-oriented regio- and enantioselective rhodium-catalyzed hydroformylation

Abstract

Hydroformylation of 1,2-disubstituted alkenes usually occurs at the α position of the directing heteroatom such as oxygen atom and nitrogen atom. By contrast, to achieve hydroformylation on the β position of the heteroatom is a tough task. Herein, we report the asymmetric rhodium-catalyzed hydroformylation of 1,2-disubstituted alkenylsilanes with excellent regioselectivity at the β position (relative to the silicon heteroatom) and enantioselectivity. In a synthetic sense, we achieve the asymmetric hydroformylation on the β position of the oxygen atom indirectly by using the silicon group as a surrogate for the hydroxyl. Density functional theory (DFT) calculations are carried out to examine energetics of the whole reaction path for Rh/YanPhos-catalyzed asymmetric hydroformylation and understand its regioselectivity and enantioselectivity. Our computational study suggests that the silicon group can activate the substrate and is critical for the regioselectivity.

Preparation and Characterization of Rh/MgSNTs Catalyst for Hydroformylation of Vinyl Acetate: The Rh0 was Obtained by Calcination

“…Hydroformylation allows atom-efficient and direct formation of aldehydes from olefins and synthesis gas, and has become a powerful synthetic route for the preparation of some key organic intermediates [1]. Recently, hydroformylation of functionalized olefins has received considerable attention [2], especially in the aspect of some special olefins, cycloolefins [3], vinyl acetate [4][5][6], dicyclopentadiene (DCPD) [7,8] and 1,3-Butadiene [9]. Because their aldehyde products, especially linear products, can be used to prepare of a variety of biologically active compounds and fine chemicals, such as chiral alcohols, acids, amines, diols, and amino alcohols [10,11].…”

Synthesis and Characterization of Rh/B–TNTs as a Recyclable Catalyst for Hydroformylation of Olefin Containing –CN Functional Group

“…The hydroformylation of functionalized alkenes is an interesting topic [ 22 ]. The functional group (FG) in functionalized alkenes (C=C–FG), in which the FG is adjacent to the C=C group, may affect catalytic hydroformylation of C=C–FG by the chelation effect of FG with the active sites of the catalyst, which may lead to a decrease in the catalytic activity of the catalyst and the object control of regioselectivity of the catalytic hydroformylation of C=C–FG becomes very difficult.…”

Phosphorus coordinated Rh single-atom sites on nanodiamond as highly regioselective catalyst for hydroformylation of olefins

“…For instance, para-methyl-and para-methoxy-substituted vinylarenes afforded relatively low regioselectivities towards the branched aldehydes, resectively, compared to styrene as well as the halo substituted para-vinylarene. 2-Vinylnaphthalene was considered as hardly reactive in toluene/water biphase system because of the large steric hindrance and the extremely low water solubility [45][46][47][48] . To our delight, 2-vinylnaphthalene was also quite reactive in the present system, giving 98% conversion, high chemoselectivity (>99%) and a b/l ratio of 6.2:1 with prolonged time (36 h).…”