Preparation and Physical Data of Racemic α-Arylaldehydes…………….. S2 (B) General Procedure for the Preparation of Catalysts 3……………………. S7 (C) General Procedure for Asymmetric Hydrogenation………………………. S8 (D) Synthesis of (S)-2-(4-Chlorophenyl)-3-methylbutanoic Acid (4)………. …S15 (E) Synthesis of BAY × 1005………………………………………………… ….S15 (F) Hydrogenation of Aldehyde 1c with D 2 ………………………………… ….S18 (G) NMR Spectra for New α-Arylaldehydes and Chiral Primary Alcohols ….S20 (H) GC or HPLC Chart for Hydrogenation Product and Other Compounds..S38 S2 General remarks. All reactions and manipulations were performed in an argon-filled glovebox (VAC DRI-LAB HE 493) or using standard Schlenk techniques. 1 H, 13 C and 31 P NMR spectra were recorded on a Varian Mercury Plus 400 spectrometer at 400

An enantioselective hydrogenation of 5-alkylidene-2,4-diketoimidazolidines (hydantoins) and 3-alkylidene-2,5-ketopiperazines catalyzed by the Rh/f-spiroPhos complex under mild conditions has been developed, which provides an efficient approach to the highly enantioselective synthesis of chiral hydantoins and 2,5-ketopiperazine derivatives with high enantioselectivities up to 99.9% ee.

This study was the first time the effects of pretreatment technology (microwave roasting, MR; oven roasting, OR; steaming roasting, SR) and processing technology (screw pressing, SP; aqueous enzymatic extraction, AEE; subcritical butane extraction, SBE) on the quality (physicochemical properties, phytochemical content, and antioxidant ability) of walnut oil were systematically compared. The results showed that the roasting pretreatment would reduce the lipid yield of walnut oil and SBE (59.53–61.19%) was the processing method with the highest yield. SR-AEE oil provided higher acid value (2.49 mg/g) and peroxide value (4.16 mmol/kg), while MR-SP oil had the highest content of polyunsaturated fatty acid (73.69%), total tocopherol (419.85 mg/kg) and total phenolic compounds (TPC, 13.12 mg/kg). The DPPH-polar and ABTS free radicals’ scavenging abilities were accorded with SBE > AEE > SP. SBE is the recommended process for improving the extraction yield and antioxidant ability of walnut oil. Hierarchical cluster analysis showed that processing technology had a greater impact on walnut oil than pretreatment technology. In addition, multiple linear regression revealed C18:0, δ-tocopherol and TPC had positive effects on the antioxidant ability of walnut oil, while C18:1n-9, C18:3n-3 and γ-tocopherol were negatively correlated with antioxidant activity. Thus, this a promising implication for walnut oil production.

A catalytic enantioselective hydrogenation of racemic a-aryloxy aldehydes via dynamic kinetic resolution has been developed by using A C H T U N G T R E N N U N G (diamine)(spirodiphosphine)ruthenium(II) chloride [RuCl 2 A C H T U N G T R E N N U N G (SDPs)A C H T U N G T R E N N U N G (diamine)] catalysts. Employing this new reaction system a variety of optically active baryloxy primary alcohols were synthesized in high yields and moderate to good enantioselectivities.Keywords: aldehydes; b-aryloxy primary alcohols; asymmetric catalysis; dynamic kinetic resolution; rutheniumThe catalytic asymmetric hydrogenation of prochiral ketones appears to be the most attractive route to produce enantiomerically enriched secondary alcohols.[1] One of the most efficient catalysts for this transformation is the chiral RuCl 2 (diphosphine)-A C H T U N G T R E N N U N G (diamine) complexes initially reported by Noyori and co-workers. [2] In the presence of base in 2-propanol, a wide range of simple ketones can be hydrogenated by chiral RuCl 2 (diphosphine)A C H T U N G T R E N N U N G (diamine) catalysts to the corresponding secondary alcohols in high enantiomeric excess at a very low catalyst loading.[3] However, due to the hydrogenation of the carbonyl group in aldehydes the latter cannot provide chiral alcohols, and people rarely consider to use an asymmetric hydrogenation of aldehydes to synthesize optically active compounds containing a primary alcohol function. [4] Recently, we reported the first example of the asymmetric hydrogenation of racemic a-aryl aldehydes via dynamic kinetic resolution (DKR) catalyzed by ruthenium complexes of chiral spirodiphosphines (SDPs) (Scheme 1).[5] As a continuing effort in this significant reaction, we herein disclose an enantioselective synthesis of chiral b-aryloxy alcohols by asymmetric hydrogenation of a-aryloxy aldehydes via DKR.The enantiomerically enriched b-aryloxy primary alcohols are a very important class of building blocks for the synthesis of a wide variety of biologically active compounds. For example, enantiomerically pure 2-aryloxy-1-propanols are starting materials for the synthesis of sorbinil homologues, [6] juvenile hormones [7] and glucokinase activating agents.[8] However, the methods for the preparation of optically active b-aryloxy primary alcohols are limited to the ringopening of chiral epoxides with phenol and its derivatives, [9] the resolution of racemic a-aryloxy alcohols with lipase-catalyzed enantioselective acylation, [10] and the conversions of lactic acid derivates.[11] Encouraged by the high activities and enantioselectivities of the RuCl 2 A C H T U N G T R E N N U N G (SDPs)A C H T U N G T R E N N U N G (diamine) catalysts in the hydrogenation of a-aryl aldehydes, we investigated the asymmetric hydrogenation of a-aryloxy aldehydes catalyzed by RuCl 2 A C H T U N G T R E N N U N G (SDPs)A C H T U N G T R E N N U N G (diamine) via DKR, targeting on the development of a new strategy for the preparation of enantiomerically enriched b-aryloxy prim...

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