Bulky Trialkylsilyl Acetylenes in the Cadiot−Chodkiewicz Cross-Coupling Reaction
作者:Joseph P. Marino、Hanh Nho Nguyen
DOI:10.1021/jo025745x
日期:2002.9.1
tert-butyldimethylsilyl (TBS), and triisopropylsilyl (TIPS) acetylenes underwent the Cadiot-Chodkiewicz cross-coupling reaction with different bromoalkynes to form a variety of synthetically useful unsymmetrical diynes in good yields. The diyne alcohol 10 was transformed regio- and stereoselectively into enynes by hydrotelluration, carbometalation, and reduction reactions.
Nickel-Catalyzed Oxidative Coupling Reactions of Two Different Terminal Alkynes Using O<sub>2</sub> as the Oxidant at Room Temperature: Facile Syntheses of Unsymmetric 1,3-Diynes
作者:Weiyan Yin、Chuan He、Mao Chen、Heng Zhang、Aiwen Lei
DOI:10.1021/ol8027863
日期:2009.2.5
Two different terminal alkynes now can be coupled together in the presence of NiCl2·6H2O/CuI by using an excess of one of the terminal alkyne substrates. The new method employed 20 mol % TMEDA as the ligand and environmentally benign O2 or air as the oxidant. It is the first example using Ni-salt as catalyst by employing air or O2 as oxidant, which led to efficient heterocoupling of two different alkynes
现在,可以通过使用过量的一种末端炔烃基质在NiCl 2 ·6H 2 O / CuI存在下将两个不同的末端炔烃偶联在一起。该新方法采用20 mol%的TMEDA作为配体,并采用对环境无害的O 2或空气作为氧化剂。这是第一个使用镍盐作为催化剂,通过使用空气或O 2作为氧化剂的例子,这导致了两个不同炔烃的有效异质偶联。
Selective synthesis of boron-substituted enynes<i>via</i>a one-pot diboration/protodeboration sequence
access enynylboronates via a Pt-catalyzed diboration/protodeboration strategy has been developed. The reaction is suitable for various silylsubstituted symmetrical and unsymmetrical 1,3-diynes, leading to π-conjugated organoboroncompounds with excellent regio- and stereoselectivity.
Investigation of an Efficient Palladium-Catalyzed C(sp)−C(sp) Cross-Coupling Reaction Using Phosphine−Olefin Ligand: Application and Mechanistic Aspects
作者:Wei Shi、Yingdong Luo、Xiancai Luo、Lei Chao、Heng Zhang、Jian Wang、Aiwen Lei
DOI:10.1021/ja8049436
日期:2008.11.5
A pi-acceptor phosphine-electron-deficient olefin ligand was found effective in promoting Pd-catalyzed C(sp)-C(sp) cross-coupling reactions. The new protocol realized the cross-coupling of a broad scope of terminal alkynes and haloalkynes in good to excellent yields with high selectivities. Electron-rich alkynes, which are normally difficult substrates in Glaser couplings, could be employed as either
Transition metal-free coupling of terminal alkynes and hypervalent iodine-based alkyne-transfer reagents to access unsymmetrical 1,3-diynes
作者:J. Schörgenhumer、M. Waser
DOI:10.1039/c8ob02375a
日期:——
A variety of unsymmetrical 1,3-diynes can easily be accessed in good yields under catalyst- and transition metal-free conditions by reacting terminalalkynes with hypervalent iodine-based electrophilic alkyne-transfer reagents.