A method for the regiodivergent arylboration of dienes is presented. These reactions allow for the formation of a diverse range of synthetically versatile products from simple precursors. Through mechanistic studies, these reactions likely operate by initial addition of a Cu–Bpin complex across the diene followed by Pd-catalyzed cross coupling with an aryl halide or pseudohalide.

A Ni-catalyzed method for arylboration is disclosed. The method allows for highly stereoselective arylboration of unactivated alkenes. The reactions utilize a simple Ni-catalyst and work with a broad range of alkenes and aryl bromides. The products represent useful intermediates for chemical synthesis due to the versatility of the C-B bond. Preliminary mechanistic details of the method are also disclosed.

A method for the Ni-catalyzed arylboration of unactivated monosubstituted, 1,1-disubstituted and trisubstituted alkenes is disclosed. The reaction is notable in that it converts highly substituted alkenes, arylbromides and diboron reagents to products that contain a quaternary carbon and a synthetically versatile carbon-boron bond with control of stereoselectivity and regioselectivity. In addition, the method is demonstrated to be useful for the synthesis of saturated nitrogen heterocycles, which are important motifs in pharmaceutical compounds. Finally, due to the unusual reactivity demonstrated, the mechanistic details of the reaction were studied with both computational and experimental techniques.

We have developed a novel synthetic method that enables the preparation of functional derivatives of heptiptycene, i.e., cavitands with two juxtaposed cavities. The homocoupling of bicyclic dibromoalkenes is promoted by Pd(OAc)2 (10%) in dioxane (100 °C) to give cyclotrimers in 27-77% yield under optimized reaction conditions (Ph3P, K2CO3, n-Bu4NBr, N2, 4 Å MS). These dual-cavity baskets show a strong π → π* absorption at 241 nm (ε = 939,000 M(-1) cm(-1)), along with a subsequent fluorescence emission at 305 nm.

A method for the regioselective 1,2-arylboration of 1,3-butadiene, a feedstock chemical, is reported. The reactions result in the formation of products that can be easily elaborated to other structures. The mechanistic details of this process are also discussed. Scheme 1. Copper/palladium-catalyzed arylboration of 1,3-dienes. Scheme 2. Mechanistic analysis of arylboration of butadiene.Communication Isr. J. Chem. 2020, 60, 394 -397 Scheme 4. Mechanistic analysis of arylboration of butadiene. Scheme 5. Representative functionalizations of an arylboration product.

Through the combination of a Ni-catalyzed alkene alkenylboration followed by hydrogenation, the synthesis of congested Csp3-Csp3-bonds can be achieved. Conditions have been identified that allow for the use of both...

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