681164-28-3Relevant articles and documents
Sandwich and half-sandwich metal complexes derived from cross-conjugated 3-methylene-penta-1,4-diynes
Vincent, Kevin B.,Gluyas, Josef B. G.,Zeng, Qiang,Yufit, Dmitry S.,Howard, Judith A. K.,Hartl, Franti?ek,Low, Paul J.
, p. 5522 - 5531 (2017/07/10)
The cross-conjugated ethynyl-vinylidene [Ph2CC(CCH){C(H)CRu(PPh3)2Cp}]PF6 ([4a]PF6), and [FcC(H)C(CCH){C(H)CRu(PPh3)2Cp}]PF6 ([4b]PF6), and ethynyl-alkynyl Ph2CC(CCH){CCRu(PPh3)2Cp} (5a), and FcC(H)C(CCH){CCRu(PPh3)2Cp} (5b) compounds (Cp = η5-cyclopentadienyl) have been prepared from reactions of the known 3-methylene-penta-1,4-diynes Ph2CC(CCH)2 (3a) and [FcCHC(CCH)2] (3b) with [RuCl(PPh3)2Cp]. The compounds derived from 3b incorporating the more electron-rich alkene proved to be unstable during work-up, and attempts to prepare bis(ruthenium) complexes from 3a and 3b or from transmetallation reactions of the bis(alkynylgold) complex FcCHC(CCAuPPh3)2 (7) with RuCl(PPh3)2Cp were unsuccessful. The related bis-and tris(ferrocenyl) derivatives Ph2CC(CCFc)2 (6a) and FcCHC(CCFc)2 (6b) were more readily obtained from Pd(ii)/Cu(i) catalysed cross-coupling reactions of FcCCH with the 1,1-dibromo vinyl complexes PhCCBr2 (1a) and FcC(H)CBr2 (1b). Cyclic voltammetry of 6a and 6b using n-Bu4N[PF6] as the supporting electrolyte shows broad, overlapping waves arising from the sequential oxidation of the ferrocenyl moieties in electronically and chemically similar environments. Electrostatic effects between the ferrocenyl moieties are enhanced in solutions of the weakly ion-pairing electrolyte n-Bu4N[B{C6H3(CF3)2-3,5}4], leading to better resolution of the individual electrochemical processes. The comparative IR spectroelectrochemical response of 6a and 6b suggest the vinyl ferrocene moiety in 6b undergoes oxidation before the ethynyl ferrocene fragments. There is no evidence of electronic coupling between the metallocene moieties and [6a]+, [6b]n+ (n = 1, 2) are best described as Class I mixed-valence compounds.
ExBox: A polycyclic aromatic hydrocarbon scavenger
Barnes, Jonathan C.,Jurí?ek, Michal,Strutt, Nathan L.,Frasconi, Marco,Sampath, Srinivasan,Giesener, Marc A.,McGrier, Psaras L.,Bruns, Carson J.,Stern, Charlotte L.,Sarjeant, Amy A.,Stoddart, J. Fraser
, p. 183 - 192 (2013/02/23)
A template-directed protocol, which capitalizes on donor-acceptor interactions, is employed to synthesize a semi-rigid cyclophane (ExBox 4+) that adopts a box-like geometry and is comprised of π-electron-poor 1,4-phenylene-bridged ("extended") bipyridinium units (ExBIPY2+). ExBox4+ functions as a high-affinity scavenger of an array of different polycyclic aromatic hydrocarbons (PAHs), ranging from two to seven fused rings, as a result of its large, accommodating cavity (approximately 3.5 A? in width and 11.2 A? in length when considering the van der Waals radii) and its ability to form strong non-covalent bonding interactions with π-electron-rich PAHs in either organic or aqueous media. In all, 11 PAH guests were observed to form inclusion complexes with ExBox4+, with coronene being the largest included guest. Single-crystal X-ray diffraction data for the 11 inclusion complexes ExBox 4+?PAH as well as UV/vis spectroscopic data for 10 of the complexes provide evidence of the promiscuity of ExBox4+ for the various PAHs. Nuclear magnetic resonance spectroscopy and isothermal titration calorimetric analyses of 10 of the inclusion complexes are employed to further characterize the host-guest interactions in solution and determine the degree with which ExBox4+ binds each PAH compound. As a proof-of-concept, a batch of crude oil from Saudi Arabia was subjected to extraction with the water-soluble form of the PAH receptor, ExBox·4Cl, resulting in the isolation of different aromatic compounds after ExBox·4Cl was regenerated.
Radiaannulenes: Synthesis, electrochemistry, and solid-state structure
Gholami, Mojtaba,Chaur, Manuel N.,Wilde, Myron,Ferguson, Michael J.,McDonald, Robert,Echegoyen, Luis,Tykwinski, Rik R.
supporting information; experimental part, p. 3038 - 3040 (2009/12/01)
Two new carbon-rich macrocycles (radiaannulenes) have been synthesized, and they possess an unsaturated carbon framework that is intermediate between that of linearly-conjugated dehydrobenzannulenes and cross-conjugated expanded radialenes. The Royal Soci
