A readily available chiral bisoxazolidine catalyzes the asymmetric Reformatsky reaction between ethyl iodoacetate and aldehydes. In the presence of 10 mol % of the ligand, dimethylzinc, and air, this method produces ethyl 3-hydroxy-3-(4-aryl)propanoates in high yields and in 75 to 80% ee at room temperature within 1 h. In contrast to aromatic substrates, relatively low ee's are obtained with aliphatic aldehydes.

The highly enantioselective addition of terminal ynamides to av ariety of isatins,c atalyzedbyabisoxazolidine copper complex under mild, base-free reaction conditions,i s described. The reaction is broad in scope,scalable,applicable to unprotected isatins,a nd provides efficient access to 3hydroxyoxindoles carrying atetrasubstituted chiral center with excellent yields and enantioselectivities.Synthetically versatile, multifunctional 3-hydroxyindolinones are obtained by hydration, partial hydrogenation, or hydroxyacyloxylation of the ynamide moiety at room temperature and exhaustive hydrogenation followed by reductive detosylation and spontaneous cyclization affords cinchonamidine alkaloids.Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.

A highly diastereoselective organocatalytic method that produces 3-fluoro-3'-hydroxy-3,3'-bisoxindoles and the corresponding 3-fluoro-3'-amino derivatives having two adjacent chirality centers from fluorooxindoles and isatins in high yields is described. The reaction occurs in protic solvents at room temperature, it can be upscaled without compromising yield and stereoselectivity, and chromatographic product purification is not required.

An efficient organocatalytic method for the synthesis of difluoromethyl and trifluoromethyl substituted β-hydroxynitriles is introduced. The decarboxylative cyanomethylation of fluorinated ketones with readily available cyanoacetic acid gives a variety of tertiary alcohols in high yields and without concomitant water elimination. The reaction occurs in the presence of catalytic amounts of triethylamine, can be upscaled and applied to chlorofluoromethyl ketones and difluoromethyl ketimines.

The enantiomers of eight axially chiral biaryls were separated by chiral HPLC. On‐column enantiomerization of 1‐(o‐tolyl)naphthalene and 2‐cyclohexyl‐2′‐dimethylaminobiphenyl was observed between 10 °C and 35 °C, generating characteristic HPLC elution profiles with a plateau between the resolved enantiomer peaks. Computer simulation of the experimentally obtained chromatograms allowed determination of the Gibbs free energies of activation, ΔG≠, as 93.2 kJ/mol and 88.4 kJ/mol, respectively.

Graphical abstract Sequential chlorination/fluorination of aromatic trifluoroacetylated ketones gives 1-aryl 2-chloro-2,4,4,4-tetrafluoro-butan-1,3-dione hydrates that are used for the synthesis of ketones and alkenes exhibiting a terminal bromochlorofluoromethyl group. The hydrates undergo detrifluoroacetylative cleavage and subsequent bromination in the presence of a copper(II)bisoxazoline catalyst, K2CO3 and NBS at room temperature. The corresponding bromochlorofluoromethyl ketones can be applied in Wittig and Horner-Wadsworth-Emmons reactions and dibromoalkenylations.

The highly enantioselective addition of terminal ynamides to a variety of isatins, catalyzed by a bisoxazolidine copper complex under mild, base‐free reaction conditions, is described. The reaction is broad in scope, scalable, applicable to unprotected isatins, and provides efficient access to 3‐hydroxyoxindoles carrying a tetrasubstituted chiral center with excellent yields and enantioselectivities. Synthetically versatile, multifunctional 3‐hydroxyindolinones are obtained by hydration, partial hydrogenation, or hydroxyacyloxylation of the ynamide moiety at room temperature and exhaustive hydrogenation followed by reductive detosylation and spontaneous cyclization affords cinchonamidine alkaloids.

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