59277-58-6Relevant academic research and scientific papers
A novel sulfonamide non-classical carbenoid: A mechanistic study for the synthesis of enediynes
Hayes, Theodore O. P.,Slater, Ben,Horan, Richard A. J.,Radigois, Marc,Wilden, Jonathan D.
, p. 9895 - 9902 (2017/12/12)
Alkynyl sulfonamides undergo sequential 1,4- then 1,2-addition/rearrangement with lithium acetylides to yield enediynes in the absence of any promoters or catalysts. Mechanistic investigations suggest that the reaction proceeds via 1,4-conjugate addition of the nucleophile to the unsaturated system to give a key alkenyl lithium species which is stabilised by an intramolecular coordination effect by a sulfonamide oxygen atom. This species can be considered a vinylidene carbenoid given the carbon atom bears both an anion (as a vinyllithium) and a leaving group (the sulfonamide). The intramolecular coordination effect serves to stabilise the vinyllithium but activates the sulfonamide motif towards nucleophilic attack by a second mole of acetylide. The resulting species can then undergo rearrangement to yield the enediyne framework in a single operation with concomitant loss of aminosulfinate.
Organocatalytic synthesis of alkynes
Zhang, Mengnan,Jia, Tiezheng,Wang, Carol Y.,Walsh, Patrick J.
supporting information, p. 10346 - 10350 (2015/09/01)
Carbon-carbon triple bonds of alkynes are ubiquitous. They serve as valuable starting materials that can be transformed into a vast array of diverse materials, with applications ranging from medicinal chemistry to electronic materials. The methods used to prepare alkynes involve stoichiometric reactions and the most popular install only a single carbon rather than uniting larger fragments. These methods are useful, but they are limited by harsh conditions or the need to prepare reagents. Introduced herein is the first catalytic method to prepare carbon-carbon triple bonds from precursors that do not contain such linkages. By coupling benzaldehyde and benzyl chloride derivatives under basic conditions with an organocatalyst, good yields of alkynes are obtained. The catalyst, a highly reactive sulfenate anion, is readily generated under the reaction conditions from air-stable precursors. This method represents an attractive organocatalytic alternative to well-established stoichiometric approaches to alkynes and to transition-metal-based alkyne functionalization methods in various applications.
Highly regio- and stereoselective synthesis of boron-substituted enynes via copper-catalyzed borylation of conjugated diynes
Li, Dingxi,Kim, Yeong Eun,Yun, Jaesook
, p. 860 - 863 (2015/03/18)
A mild copper-catalyzed regio- and stereoselective monoborylation of conjugated diynes with bis(pinacolato)diboron that affords enynylboronates is reported. The reaction is efficient for different types of conjugated diynes including unsymmetrical diynes
Synthesis of polysubstituted enynes through iron-catalyzed carbomagnesiation of conjugated diynes
Ilies, Laurean,Yoshida, Takumi,Nakamura, Eiichi
supporting information, p. 527 - 530 (2014/03/21)
Symmetrical and unsymmetrical conjugated diynes are chemo-, regio-, and stereoselectively carbomagnesiated with a ?Grignard reagent at room temperature in the presence of a catalytic amount of FeCl2 without the need for an external ligand. The resulting magnesium intermediate can be further functionalized to give polysubstituted 1,3-enyne derivatives. Georg Thieme Verlag Stuttgart New York.
A regio- and stereoselective synthesis of trisubstituted alkenes via gold(i)-catalyzed hydrophosphoryloxylation of haloalkynes
Chary, Bathoju Chandra,Kim, Sunggak,Shin, Doosup,Lee, Phil Ho
, p. 7851 - 7853 (2011/09/12)
A new stereoselective synthesis of trisubstituted alkenes is developed. Hydrophosphoryloxylation of haloalkynes provides Z-alkenyl halophosphates, which undergo Pd-catalyzed consecutive cross-coupling reactions to afford regio- and stereodefined trisubsti
Aldehyde addition to 1,3-butadiyne-derived zirconacyclocumulenes: Stereoselective synthesis of cis-[3]cumulenols
Fu, Xiaoping,Liu, Yuanhong,Li, Yuxue
experimental part, p. 3012 - 3018 (2010/10/03)
The direct addition of aldehydes to zirconacyclocumulenes generated through the coupling reactions of benzynezirconocenes with 1,3-butadiynes is achieved cleanly under controlled reaction conditions, which provids a highly stereoselective method for the synthesis of tetra-substituted [3]cumulenols. DFT calculations suggest that there is an equilibrium between seven-membered zirconacyclocumulene (3) and the less stable but more reactive five-membered α-alkynylzirconaindene (2) in the process. The aldehyde reacts with the five-membered zirconaindene intermediate through a cyclic SE2' pathway to afford cumulenol products after hydrolysis.
Vinyl Cations in Organic Synthesis. Part 2. A Novel Synthesis of Methylene-1H-indenes (Benzofulvenes) by Cyclisation of Phenyl-substituted But-1-en-3-ynes
Marcuzzi, Franco,Azzena, Ugo,Melloni, Giovanni
, p. 2957 - 2960 (2007/10/02)
A series of phenyl-substituted but-1-en-3-ynes has been prepared and their reactivity toward acid-catalysed cycloisomerisation investigated.In boiling dichloromethane of 1,2-dibromoethane in the presence of a catalytic amount of methanesulfonic acid, 1,1,
