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Herein, a general applicable method for the atom‐economic catalytic construction of a broad range of 1,2‐dialkylaminoethers is presented. By taking advantage of an elaborated protocol for the photocatalyzed anti‐Markovnikov selective hydroamination of nonactivated alkenes, a series of 1,2‐dialkylaminoethers was accessed by reacting readily available vinyl ethers with secondary alkyl amines. It was demonstrated that the reaction can be performed at low catalyst loadings while the commonly employed triisopropylbenzene thiol Hydrogen Atom Transfer (HAT)‐catalyst was replaced by an easier accessible mesityl thiol. Furthermore, the inexpensive and readily available diphenyl disulfide was proven as suitable HAT‐catalyst alternative for the efficient hydroamination of simple vinyl ethers. [ABSTRACT FROM AUTHOR]

A copper(I)/phosphine system that homogeneously catalyses the alkynylation of formaldehyde with acetylene or terminal alkynes is reported. Using acetylene at atmospheric pressure, the catalyst consisting of <1 mol% copper(I) phenylacetylide and a trialkyl bisphosphine ligand shows a high selectivity towards the formation of propargyl alcohol rather than 1,4‐butynediol, which is not reported for common heterogeneous copper acetylide catalysts. The biphasic water/toluene reaction mixture allows the separation of targeted products with the aqueous layer and catalyst recycling via the organic layer. [ABSTRACT FROM AUTHOR]

Enantiopure a-hydroxy carbonyl compounds are common scaffolds in natural products and pharmaceuticals. Although indirect approaches towards their synthesis are known, direct asymmetric methodologies are scarce. Herein, we report the first direct asymmetric a-hydroxylation of a-branched ketones through enol catalysis, enabling a facile access to valuable a-keto tertiary alcohols. The transformation, characterized by the use of nitrosobenzene as the oxidant and a new chiral phosphoric acid as the catalyst, delivers a good scope and excellent enantioselectivities. [ABSTRACT FROM AUTHOR]

We report a Brønsted acid mediated direct α-hydroxylation of cyclic α-branched ketones via a tandem aminoxylation/N-O bond-cleavage process. Nitrosobenzene is used as the oxidant and subsequently promotes the liberation of the free alcohol. The desired products could be isolated in moderate to good yields at a maximum tested scale of 10 mmol. Derivatizations of the obtained products are presented. [ABSTRACT FROM AUTHOR]

We report a highly enantioselective α-amination of α- branched ketones catalyzed by a chiral phosphoric acid employing azodicarboxylates as reagents. The desired products were obtained in good to excellent yields and enantioselectivities. [ABSTRACT FROM AUTHOR]