A ligand-controlled regiodivergent Cu-catalyzed aminoboration of unactivated terminal alkenes with diboron reagents and hydroxylamines has been developed. The xantphos-ligated CuCl complex guides the boron and amino groups to the terminal and internal positions, respectively. On the other hand, the opposite regioisomers are selectively obtained under the N-heterocyclic carbene-based IPrCuBr catalysis. The two Cu catalysts can readily transform simple and abundant terminal alkenes into highly valuable β-borylalkylamines regiodivergently.

A copper-catalyzed aminoboration of bicyclic alkenes, including oxa- and azabenzonorbornadienes, has been developed. With this method, amine and boron moieties are simultaneously introduced at an olefin with exo selectivity. Subsequent stereospecific transformations of the boryl group can provide oxygen- and nitrogen-rich cyclic molecules with motifs that may be found in natural products or pharmaceutically active compounds. Moreover, a catalytic asymmetric variant of this transformation was realized by using a copper complex with a chiral bisphosphine ligand, namely (R,R)-Ph-BPE.

A Cu-catalyzed aminoboration of 1-methylenecyclopropanes with bis(pinacolato)diboron and O-benzoyl-N,N-dialkylhydroxylamines has been developed. The Cu catalysis provides a rapid and concise access to (borylmethyl)cyclopropylamines in a highly regio- and diastereoselective manner. The products obtained can be useful building blocks for the synthesis of potential antidepressants, trans-2-arylcyclopropylamine derivatives.

A copper‐catalyzed aminoboration of bicyclic alkenes, including oxa‐ and azabenzonorbornadienes, has been developed. With this method, amine and boron moieties are simultaneously introduced at an olefin with exo selectivity. Subsequent stereospecific transformations of the boryl group can provide oxygen‐ and nitrogen‐rich cyclic molecules with motifs that may be found in natural products or pharmaceutically active compounds. Moreover, a catalytic asymmetric variant of this transformation was realized by using a copper complex with a chiral bisphosphine ligand, namely (R,R)‐Ph‐BPE.

We have developed sequential Zr/Cu catalysis involving regioselective hydroboration and electrophilic amination for the formal anti-Markovnikov hydroamination of terminal aryl alkynes. The reaction system can provide a facile access to enamines from terminal acetylenes with high regioselectivity under mild conditions.Enamines are important building blocks in organic synthesis because of their versatile reactivity directed toward alkylations, cycloadditions, and some related bond-forming reactions for heterocycle synthesis.1 In general, enamines are prepared by condensation of the corresponding aldehydes or ketones and amines in the presence of Brønsted acids or Lewis acids. However, due to relatively harsh reaction conditions, the above processes sometimes suffer from low functional compatibility. On the other hand, transition-metal-catalyzed hydroamination of alkynes with amines has recently received significant attention because it can complement the traditional condensation methodology and provide functional-group-tolerant approach to the target enamines. To date, a variety of catalyst systems have been reported. 3 However, in view of regioselectivity and efficiency, there still remains some room for the anti-Markovnikov hydroamination of terminal alkynes. Although 4 Ru-, 5 and Zrbased 6 catalysts have been successfully employed, 7 most of them require elevated temperature.8 Thus, further developments appear to be desired.Meanwhile, our group 9 and others 10 have recently focused on the unique reactivity of chloramines and hydroxylamine derivatives and succeeded in the catalytic CN bond formation through an electrophilic amination. In this context, we envisioned that a combination of regioselective hydroboration of terminal alkynes and electrophilic amination of preformed alkenylborane intermediates could be a good alternative to the above hydroamination protocols. Here, we report sequential Zr/ Cu catalysis for a formal anti-Markovnikov hydroamination of terminal aryl alkynes. The process involves Zr-catalyzed hydroboration with pinacolborane and Cu-catalyzed electrophilic amination with O-benzoylhydroxylamines, leading to the corresponding enamines regioselectively under very mild conditions (Scheme 1). 11To establish the second electrophilic amination step shown in Scheme 1, we first chose (E)-4,4,5,5-tetramethyl-2-styryl-1,3,2-dioxaborolane (0.25 mmol) and O-benzoyl-N,N-diethylhydroxylamine (1a, 0.30 mmol) as model substrates and extensively screened various reaction parameters such as catalysts, bases, and solvents. It was found that the reaction proceeded in THF smoothly even at room temperature in the presence of a catalytic amount of Cu(OAc) 2 ¢OH 2 together with several phosphorous ligands using LiOt-Bu as the base (Scheme 2).Among the phosphorus ligands we tested, P(OEt) 3 , PPh 3 , and 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (xantphos) showed better activity, and the corresponding enamine 2a was obtained in 5965% yields, as judged by 1 H NMR. In the case of P(OEt) 3 , when 1a was used as...