Direct Synthesis of Alkenylboronates from Alkenes and Pinacol Diboron via Copper Catalysis
作者:Wenkui Lu、Zengming Shen
DOI:10.1021/acs.orglett.8b03599
日期:2019.1.4
We report an efficient approach for the direct synthesis of alkenylboronates using copper catalysis. The Cu/TEMPO catalyst system (where TEMPO = (2,2,6,6-tetramethylpiperidin-1-yl)oxyl) exhibits both excellent reactivity and selectivity for the synthesis of alkenylboronates, starting from inexpensive and abundant alkenes and pinacol diboron. This approach allows for the direct functionalization of
A magnesium‐catalyzed hydroboration of alkynes providing good yields and selectivities for a wide range of terminal and symmetrical and unsymmetrical internal alkynes has been developed. The compatibility with many functional groups makes this magnesium catalyzed procedure attractive for late stage functionalization. Experimental mechanistic investigations and DFT calculations reveal insights into
trans-Arylvinylboronate derivatives are important synthesisblocks in natural products, pharmaceuticals and organic materials. There are only a few reaction conditions that could selectively provide trans-arylvinylboronates by Heck coupling of pinacol vinylboronate and aryl halides. Here we report an efficient and versatile method of palladium catalyzed cross-coupling between pinacol vinylboronate and
N‐heterocyclic carbene‐cappedcyclodextrin (ICyD) ligands, α‐ICyD and β‐ICyD derived from α‐ and β‐cyclodextrin, respectively give opposite regioselectivities in a copper‐catalyzed hydroboration. The site‐selectivity results from two different mechanisms: the conventional parallel one and a new orthogonal mechanism. The shape of the cavity was shown not only to induce a regioselectivity switch but
Soluble Platinum Nanoparticles Ligated by Long-Chain N-Heterocyclic Carbenes as Catalysts
作者:Luis M. Martínez-Prieto、Lena Rakers、Angela M. López-Vinasco、Israel Cano、Yannick Coppel、Karine Philippot、Frank Glorius、Bruno Chaudret、Piet W. N. M. van Leeuwen
DOI:10.1002/chem.201702288
日期:2017.9.18
Soluble platinum nanoparticles (Pt NPs) ligated by two different long-chain N-heterocycliccarbenes (LC-IPr and LC-IMe) were synthesized and fully characterized by TEM, high-resolution TEM, wide-angle X-ray scattering (WAXS), X-ray photoelectron spectroscopy (XPS), and solution NMR. The surface chemistry of these NPs (Pt@LC-IPr and Pt@LC-IMe) was investigated by FT-IR and solid state NMR using CO as