324529-86-4Relevant academic research and scientific papers
Synthesis of five- and six-membered benzocyclic ketones through intramolecular alkene hydroacylation catalyzed by Nickel(0)/N-Heterocyclic Carbenes
Hoshimoto, Yoichi,Hayashi, Yukari,Suzuki, Haruka,Ohashi, Masato,Ogoshi, Sensuke
supporting information, p. 10812 - 10815 (2013/01/15)
Getting some closure: Mechanistic studies supported the participation of an oxanickelacycle complex in the hydroacylation step of the title reaction, which proceeds without decarbonylation even in the absence of well-known chelation assistance by heteroatoms. Copyright
Ring-closure reactions of 1,2-diaza-4,5-benzoheptatrienyl metal compounds: Experiment and theory
Kleine, Tillmann,Bergander, Klaus,Froehlich, Roland,Wibbeling, Birgit,Wuerthwein, Ernst-Ulrich
, p. 1979 - 1991 (2011/05/07)
2-Alkenylbenzylidene hydrazones 5a-m, which are accessible in good to excellent yields in a four-step synthesis, are converted into 1,2-diaza-4,5-benzoheptatrienyl metal compounds 1a-m by treatment with KO-t-Bu as base. These metal compounds undergo the various types of reactions in good yields and exclusively depending on the nature of substituents R1 and R3. Thus, metal compounds 1a-c carrying alkyl substituents R 1 and R3 form 3H-benzodiazepines 6a-c after electrophilic quench of the intermediate cyclic anion 7 in a 7-endo-trig electrocyclic reaction with a moebius aromatic transition structure 1--TS. Similarly, a benzothienyl derivative 5n is converted into diazepine 6d. Potassium compounds 1d-h, which are N-methyl and aryl substituted at R 3, form 1,2-dihydrophthalazines 8a-e in a predominantly charge-controlled 6-exo-trig cyclization reaction. In contrast, aryl-aryl-substituted systems 5i-m did not lead to cyclic products upon deprotonation, but the intermediate open-chain metal compounds 1i-m were trapped by acid chlorides at N1 to yield the hydrazides 10a-e. We interpret thermodynamics and kinetics of these reactions in the context of the Baldwin rules on the basis of quantum chemical calculations and discuss the transition structures considering the results of NICS and NBO-charge calculations. Examples of the products 6, 8, and 10 could be characterized by X-ray diffraction.
Efficient platinum(II) catalyzed hydroformylation reaction in water: Unusual product distribution in micellar media
Gottardo, Marina,Scarso, Alessandro,Paganelli, Stefano,Strukul, Giorgio
experimental part, p. 2251 - 2262 (2010/12/25)
The hydroformylation of a variety of terminal and internal alkenes is efficiently performed by cationic platinum triflate complexes of the type [P2Pt(H2O)2](OTf)2 under mild conditions in an aqueous micellar medium. The use of surfactants is essential to ensure dissolution of the catalyst and substrate in water with catalysts being positioned on the anionic surface of the micelles. Aldehydes are obtained with linear to branched ratios up to >99:1. With styrene derivatives also the corresponding benzaldehydes are formed. The catalyst can be separated by extraction of the organic products with hexane and recycled for at least four times with only a modest loss of activity and no effect on selectivity.
Palladium-catalyzed cross-coupling of aryl chlorides with alkenylboronic acids with low E/Z isomerization
Thimmaiah, Muralidhara,Zhang, Xiang,Fang, Shiyue
, p. 5605 - 5607 (2008/12/22)
Using a bulky electron-rich monodentate benzoferrocenyl phosphine as supporting ligand, an efficient protocol for stereoselective palladium-catalyzed Suzuki-Miyaura cross-coupling of aryl chlorides with alkenylboronic acids was uncovered. Using this protocol, both trans- and cis-alkenylboronic acids can be coupled with high stereoselectivity giving the corresponding vinylarenes in good to quantitative yields. Electron-poor and -rich aryl chlorides including highly hindered ones are all suitable substrates for the reaction.
