Copper-Catalyzed Amino Lactonization and Amino Oxygenation of Alkenes Using O-Benzoylhydroxylamines

Abstract

A copper-catalyzed amino lactonization of unsaturated carboxylic acids has been achieved as well as the analogous intermolecular three-component amino oxygenation of olefins. The transformation features mild conditions and a remarkably broad substrate scope, offering a novel and efficient approach to construct a wide range of amino lactones as well as 1,2-amino alcohol derivatives. Mechanistic studies suggest that the reaction proceeds via a distinctive O-benzoylhydroxylamine-promoted electrophilic amination of alkenes.

Electrochemical Azidooxygenation of Alkenes Mediated by a TEMPO–N3 Charge-Transfer Complex

“…When compared to other existing catalytic reactions that convert alkenes to vicinal amino alcohols, 19 our new method displays complementary scope, regioselectivity, and stereoselectivity. For instance, the classical Os-catalyzed aminohydroxylation encounters problematic regioselectivity with certain types of alkenes, while sterically hindered substrates frequently undergo undesirable dihydroxylation.…”

“…20 Another elegant example is the Fe-catalyzed aminooxygenation using oxaziridines. 19c However, this protocol has primarily been applied to activated alkenes (e.g., styrenes and conjugate dienes) and shows decreased efficiency with unactivated alkenes. It is also noteworthy that both aforementioned methods are stereospecific, with both O and N groups added to the same side of the C═C bond.…”

Transition‐Metal‐Catalyzed Electrophilic Amination: Application of O‐Benzoylhydroxylamines in the Construction of the C−N Bond

“…Very recently, Wang group achieved another annulative amination, converting unsaturated carboxylic acids to a variety of amino lactones (Scheme ) . This copper‐catalyzed amino lactonization showed dramatically broad substrate scope, strongly promoting its practicability.…”

“…Very recently,W ang group achieved another annulative amination,c onverting unsaturated carboxylic acids to av ariety of amino lactones (Scheme 45). [35] This copper-catalyzeda mino lactonization showedd ramatically broad substrate scope, strongly promoting its practicability.A dditionally,a ni ntermolecular three-component amino oxygenation of styrenes was also described( Scheme 46). Various 2-aminoethyl esters were Scheme40.…”

Synthesis of β‐Boryl‐α‐Aminosilanes by Copper‐Catalyzed Aminoboration of Vinylsilanes

“…The N-pentenylamine furnished the usual product 3ff,t hus suggesting an aminyl radical pathway is unlikely. [18] Although the Cu-based system accommodated cyclic amines such as piperidine, morpholine,a cetal-protected piperidone, N-Boc piperazine, and azepane (3fg-3fk), all products were sensitive to silica gel in the column chromatography.H owever,w ec ould pleasingly isolate them as the corresponding alcohol (3fh-O, 3fj-O,a nd 3fk-O)o rm ore stable boryl derivatives such as B(dan) (dan = 1,8-diaminonaphthyl; 3fh-Bdan) [19] and BF 3 À (3fg-BF 3 and 3fi-BF 3 ). [8a, 20] Particularly in the last cases,t he chromatographic purification was not necessary,a nd simple filtration furnished analytically pure internal ammonium borate salts 3fg-BF 3 and 3fi-BF 3 .…”