Conversion of Bromoalkenes into Alkynes by Wet Tetra-n-butylammonium Fluoride
摘要:
Tetra-n-butylammonium fluoride was found to be a mild and efficient base for the elimination reaction of bromoalkenes. Treatment of 1,1-dibromoalkenes, (Z)-1-bromoalkenes, and internal bromoalkenes with 5 equiv of TBAF center dot 3H(2)O in DMF yielded terminal and internal alkynes in high yields without undue regard to the presence of water.
for the ortholithiation of 3-aryl and 3-styryl furans has been uncovered wherein lithiation occurs preferentially at the sterically encumbered 2-position. The results are attributed, at least in part, to stabilization of the intermediate furyl anion by through-space donation of pi-electron density from the substituent appended at the 3-position to the lithium cation. This ortholithiation reaction
Copper(I) Hydroxyapatite Catalyzed Sonogashira Reaction of Alkynes with Styrenyl Bromides. Reaction of <i>cis</i>-Styrenyl Bromides Forming Unsymmetric Diynes
作者:Debasree Saha、Tanmay Chatterjee、Manabendra Mukherjee、Brindaban C. Ranu
DOI:10.1021/jo3015819
日期:2012.10.19
terminal alkynes and styrenyl bromides has been achieved under the catalysis of hydroxyapatite-supported copper(I). The trans-styrenyl bromides produce the usual trans-enyne products, whereas the cis-styrenyl bromides lead to unsymmetric 1,3-diynes by the cross coupling of terminal alkyne and the alkyne generated from the cis-styrenyl bromide. A series of trans-enynes and unsymmetric 1,3-diynes have been synthesized
Ruthenium‐Catalyzed Synthesis of Aryl and Alkenyl Halides from Fluorosulfonates
作者:Clotilde Plaçais、Sherif J. Kaldas、Morgan Donnard、Armen Panossian、David Bernier、Sergii Pazenok、Frédéric R. Leroux
DOI:10.1002/chem.202301420
日期:2023.7.20
coupling reactions has increased over the past decade. Surprisingly, the use and synthesis of alkenyl fluorosulfonates is still poorly described. In this paper, the advantageous use of aryl and alkenyl fluorosulfonates instead of the corresponding triflates is reported to synthesize aryl and alkenyl halidesusinghalidesalts and commercially available ruthenium catalysts.
Aryl and vinyl cyclopropanes through the in situ generation of B-cyclopropyl-9-BBN and its Suzuki–Miyaura coupling
作者:John A. Soderquist、Ramon Huertas、Gisela Leon-Colon
DOI:10.1016/s0040-4039(00)00605-5
日期:2000.6
Dihydroboration of propargyl bromide with 9-BBN-H followed by treatment of the adduct with aqueous sodium hydroxide affords the hydroxy(cyclopropyl)borate complex (1), which undergoes efficient palladium-catalyzed cross-coupling to produce a variety of aryl and vinyl cyclopropanes (2) in good to excellent yields. (C) 2000 Elsevier Science Ltd. All rights reserved.
Synthesis of chiral bis-homoallylic epoxides. A new class of lepidopteran sex attractants