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51.
James Courmarcel Gildas Le Gland Loic Toupet Fr d ric Paul Claude Lapinte 《Journal of organometallic chemistry》2003,670(1-2):108-122
The synthesis of the new (η2-dppe)(η5-C5Me5)Fe---CC---1,3-(C6H4X) (m-2a/2b; X=F/Br) and (η2-dppe)(η5-C5Me5)Fe---CC---1,4-(C6H4I) (2c) complexes, as well as the solid-state structure of the known (η2-dppe)(η5-C5Me5)Fe---CC---1,4-(C6H4F) (2a) complex are described. The catalytic coupling reactions of the bromo complexes with various alkynes were next investigated. Starting from the known (η2-dppe)(η5-C5Me5)Fe---CC---1,4-(C6H4Br) complex (2b), the synthesis of the (η2-dppe)(η5-C5Me5)Fe---CC---1,4-(C6H4)---CC---H complex (6d) and of the corresponding silyl-protected precursors (η2-dppe)(η5-C5Me5)Fe---CC---1,4-(C6H4)CC---SiR3 (6b/6c; R=iPr/Me) are reported. By use of lithium---bromine exchange reactions on 2b, the silyl- (7a; E=Si; R=Me) and tin- (7b–7d; E=Sn; R=Me, Bu, Ph) substituted analogues (η2-dppe)(η5-C5Me5)Fe---CC---1,4-(C6H4)ER3 are also isolated. The spectroscopic and electrochemical characterisations of all these new Fe(II)/Fe(III) redox-active building blocks are presented and the electronic substituent parameters for the “(η2-dppe)(η5-C5Me5)Fe---CC” group are determined by means of 19F-NMR. 相似文献
52.
Naoki Kakusawa 《Journal of organometallic chemistry》2005,690(12):2956-2966
The reaction of ethynylstibanes (1a-g) with vinyl halides or triflate in the presence of a palladium catalyst led to the formation of cross-coupling products (5a-g, 10-12) in good to moderate yield, along with homo-coupling products (6a-g). A similar reaction of ethynyldiphenylstibane (1a) with aryl iodides (13a-i) also gave cross-coupling products (14a-i), although the yields were relatively low. The yields of the cross-coupling products were highly dependent on the nature of the solvent employed, and good results were obtained when the reaction was carried out in HMPA or amines such as diethylamine and morpholine. The results imply that HMPA and amine used as solvents facilitate transmetallation of the ethynyl group on 1 to the palladium by intermolecular coordination between antimony and oxygen (for HMPA) or nitrogen (for amine). 相似文献
53.
The enthalpies of mixing of some n-nitriles (from acetonitrile to valeronitrile) aqueous solutions with dodecyltzimethylammonium bromide, sodium dodecylsulfate and dodecyltzimethylammonium oxide micellar solutions were determined. The measurements were performed by systematically changing the surfactant concentration at a given solute concentration. The experimental enthalpies were rationalized in terms of the standard enthalpy of transfer of solute from the aqueous to the micellar phase and of the distribution constant between the two phase. Information on the effect of the nature of the surfactant on the standard thermodynamic quantities of transfer(G
t
o
, H
t
o
, TS
t
o
) is reported. The present data are compared to those previously reported for primary alcohols and the solubilizing properties shown by the different types of micelles are discussed. 相似文献
54.
Aryl bromides (3 equiv) were coupled efficiently with triarylbismuths (1 equiv) in an atom-efficient way using the Pd(OAc)2/PPh3 catalytic system in the presence of K3PO4 as base in DMF at 90 °C, providing excellent yields of the cross-coupled biaryls in short reaction times. 相似文献
55.
Oxidation of sulfides to sulfoxides and sulfones was achieved in moderate to high yields with a good selectivity, by using Fe2O3, MnO2, Cu(OH)2 and Cu(OAc)2 as catalyst, with molecular oxygen in the presence of isovaleraldehyde under mild conditions. 相似文献
56.
Bis-dithianylalkanols and dimers are formed in preparation of 2-lithio-1,3-dithianes due to the presence of oxidising impurity in n-BuLi (perhaps n-BuOOLi). 相似文献
57.
58.
Guangzhou Lu Limin Yang Liqiang Wu 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):403-408
Abstract A simple, inexpensive, and efficient one-pot synthesis of 2-arylthiazoline derivatives under solvent-free conditions using a catalytic amount of 1-butyl-3-methylimidazolium tribromide with excellent product yields is reported. This methodology provides easy, quantitative access to various 2-arylthiazoline derivatives, using environmentally benign 1-butyl-3-methylimidazolium tribromide as a catalyst. 相似文献
59.
60.
Houssam Trabulsi 《合成通讯》2013,43(14):2123-2134
Reaction of γ-phenyl-β,γ-unsaturated hydroxamates with bis(collidine)bromine(I) hexafluorophosphate led to the formation of cyclic bromo imidates. Reaction of these with triethylamine led to the formation of 3-cyano-2-propen-1-ones with good yields by a fragmentation reaction. 相似文献