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Pablo Etayo et al.
Chemical Society reviews, 42(2), 728-754 (2012-11-08)
During the last few decades, rhodium-catalysed asymmetric hydrogenation of diverse alkene classes has emerged as a powerful synthetic tool in the pharmaceutical industry, contributing to the manufacturing of chiral drugs, recent drug candidates for clinical trials, and major synthetic precursors...
P Andrew Evans et al.
Organic letters, 15(8), 1798-1801 (2013-04-02)
A concise and highly convergent three-step total synthesis of the lactarane natural product, pyrovellerolactone, is described. The key step involves a regio- and diastereoselective rhodium-catalyzed [(3 + 2) + 2] carbocyclization of an alkenylidenecyclopropane with a 4-hydroxybut-2-ynoate followed by an...
Xiaocong Xie et al.
Organic letters, 15(7), 1500-1503 (2013-03-22)
Allylic cyclopropenecarboxylates undergo ring expansion reactions to give 2-allyloxyfuran intermediates, which subsequently rearrange to Δ(β,γ) butenolides via a Claisen rearrangement or to the corresponding Δ(α,β) butenolides via further Cope rearrangement. Also described are methods for chirality transfer in the rearrangement...
Rakesh Kumar Gupta et al.
Inorganic chemistry, 52(7), 3687-3698 (2013-03-13)
The synthesis of four novel heteroleptic dipyrrinato complexes [(η(6)-arene)RuCl(2-pcdpm)] (η(6)-arene = C6H6, 1; C10H14, 2) and [(η(5)-C5Me5)MCl(2-pcdpm)] (M = Rh, 3; Ir, 4) containing a new chelating ligand 4-(2-methoxypyridyl)-phenyldipyrromethene (2-pcdpm) have been described. The complexes 1-4 have been fully characterized...
Nicolai Cramer
Chimia, 66(11), 869-872 (2013-02-12)
The direct functionalization of non-activated C-H bonds, especially in an enantioselective manner, requires metal catalysts equipped with ligands with specifically designed properties. Examples for asymmetric C(sp(2))-H and C(sp(3))-H functionalizations using palladium- and rhodium catalysts are shown. This work was rewarded...
Ramya Sambasivan et al.
Chirality, 25(9), 493-497 (2013-06-12)
Dirhodium metallopeptides have been developed as selective catalysts for asymmetric cyclopropanation reactions. A selective ligand sequence has been identified by screening on-bead metallopeptide libraries in a 96-well plate format. Efficient ligand synthesis and screening allows a 200-member library to be...
Andreja Bakac
Dalton transactions (Cambridge, England : 2003), (13)(13), 1589-1596 (2006-03-21)
In aqueous solutions, as in organic solvents, rhodium hydrides display the chemistry of one of the three limiting forms, i.e. {Rh(I)+ H+}, {Rh(II)+ H.}, and {Rh(III)+ H-}. A number of intermediates and oxidation states have been generated and explored in...
Tao Zhang et al.
Organic letters, 15(24), 6294-6297 (2013-11-28)
Rh(III)-catalyzed olefination of N-sulfonyl imines using acrylates and styrenes has been achieved for the synthesis of ortho-olefinated benaldehydes. This reaction proceeds via a chelation assisted C-H olefination/in situ hydrolysis process.
G Pótári et al.
Langmuir : the ACS journal of surfaces and colloids, 29(9), 3061-3072 (2013-02-08)
High-aspect-ratio titanate nanotubes (NT) and nanowires (NW) were produced by the hydrothermal conversion of TiO2 at 400 K. The titanate morphology was studied by high-resolution transmission electron microscopy (HRTEM). The formation of ordered titanate nanoobjects depended on the time of...
Juliane Keilitz et al.
Organic letters, 15(5), 1148-1151 (2013-02-21)
A new enantioselective rhodium-catalyzed domino reaction is described that gives access to fused heterocycles by desymmetrization of alkyne-tethered cyclohexadienones. Two new C-C bonds and two stereocenters are formed in one step with good enantioselectivity. In contrast to prior reports, it...
Marcella Lemos Brettas Carneiro et al.
Journal of nanobiotechnology, 11, 4-4 (2013-02-19)
Magnetic fluids containing superparamagnetic iron oxide nanoparticles represent an attractive platform as nanocarriers in chemotherapy. Recently, we developed a formulation of maghemite nanoparticles coated with rhodium (II) citrate, which resulted in in vitro cytotoxicity enhanced up to 4.6 times when...
Vladimir V Grushin
Accounts of chemical research, 43(1), 160-171 (2009-10-01)
Although springing from two established fields, organometallic chemistry and fluorine chemistry, organometallic fluorine chemistry is still in its early stages. However, developments in this area are expected to provide new tools for the synthesis of selectively fluorinated organic compounds that...
Salah Al Zadjali et al.
International journal of clinical and experimental medicine, 8(5), 7160-7167 (2015-07-30)
Lead is a widely-spread environmental pollutant and a commonly-used industrial chemical that can cause multisystemic adverse health effects. However, the effects of lead exposure on diabetic animals have not been reported so far. The aim of this study is to...
Casi M Schienebeck et al.
Chemical communications (Cambridge, England), 49(26), 2616-2618 (2013-02-26)
We systematically examined the effect of different esters on the rhodium-catalyzed intermolecular [5+2] cycloaddition of 3-acyloxy-1,4-enynes and alkynes with a concomitant 1,2-acyloxy migration. Significant rate acceleration was observed for benzoate substrates bearing an electron-donating substituent. The cycloaddition can now be...
María Garrido et al.
Chembiochem : a European journal of chemical biology, 16(4), 641-650 (2015-02-14)
Several diseases involve alterations in sphingolipid metabolism, so the development of tools for the analysis of sphingolipid metabolic fluxes is of interest. In this work, ω-azidosphingolipids 1-3 have been synthesized and tested as tracers in live cells. The synthesis starts...
The ONIOM Method and Its Applications.
Lung Wa Chung et al.
Chemical reviews, 115(12), 5678-5796 (2015-04-09)
Dipti Patel et al.
Dalton transactions (Cambridge, England : 2003), 44(31), 14159-14177 (2015-07-18)
Treatment of anhydrous FeX2 (X = Cl, Br, I) with one equivalent of bis(diphenylphosphino)ethane (dppe) in refluxing THF afforded analytically pure white (X = Cl), light green (X = Br), and yellow (X = I) [FeX2(dppe)]n (X = Cl, ;...
Xiangyang Bi et al.
Journal of hazardous materials, 297, 191-197 (2015-05-11)
In this study, ground surface dust samples from two contrasting areas, a former zinc smelting area in Guizhou Province and a common urban district in Wuhan city, Hubei Province, China, were assessed for in vitro Pb bioaccessibility using a physiologically...
C Afonso et al.
Environmental research, 143(Pt B), 130-137 (2015-05-13)
The Se, Hg, and methylmercury (MeHg) levels in raw, cooked (boiled and grilled), and canned tuna (Thunnus spp.) were determined before and after an in vitro digestion, thereby enabling the calculation of the respective bioaccessibility percentages. A risk-benefit evaluation of...
Xian-Ying Shi et al.
Organic letters, 15(7), 1476-1479 (2013-03-09)
A novel rhodium(III)-catalyzed direct functionalization of the ortho-C-H bond of aromatic ketone derivatives and an intramolecular cyclization sequence produced indene derivatives in moderate to good yields. This cascade cyclization involves a conjugate addition of α,β-unsaturated ketone and subsequent aldol condensation....
Yicheng Xu et al.
Journal of nanoscience and nanotechnology, 13(7), 5048-5052 (2013-08-02)
Thermoregulated ionic liquid and organic biphasic system composed of ionic liquid [CH3(OCH2 CH2)22N+Et3][CH3SO3-] (abbreviated as IL(PEG1000)) containing IL(PEG1000)-stabilized Rh nanoparticles and organic solvent, which allows for not only highly efficient homogeneous reaction but also an easy biphasic separation, was applied...
Jingjing Wang et al.
The Journal of organic chemistry, 78(17), 8217-8231 (2013-06-08)
A new method for building aryl aryl ketones containing heterocyclic rings through chelation-assisted C-O bond activation catalyzed by a rhodium complex has been developed. In this reaction, methyl quinoline-8-carboxylate, methyl quinoxaline-5-carboxylate, and their derivatives were reacted with an excess amount...
Nicolas P E Barry et al.
Chemical Society reviews, 41(8), 3264-3279 (2012-02-07)
This review describes how the incorporation of dicarba-closo-dodecarboranes into half-sandwich complexes of ruthenium, osmium, rhodium and iridium might lead to the development of a new class of compounds with applications in medicine. Such a combination not only has unexplored potential...
Malene Outzen et al.
Nutrients, 7(1), 608-624 (2015-01-20)
Selenium status of the Danish population is below that assumed optimal for the suggested protective effects against chronic diseases, including certain cancers. Fish and shellfish are important dietary sources of selenium in Denmark. We investigated the effect of increased fish...
Xinfang Xu et al.
Chemical communications (Cambridge, England), 49(27), 2762-2764 (2013-02-28)
A highly diastereoselective formal [3+2+1]-cycloaddition reaction that produces multi-functionalized bicyclic pyrazolidinone derivatives is achieved in moderate to high yield by Rh2(4S-MPPIM)4-catalyzed reaction of azomethine imines with two molecules of a diazo ketone.
D Sirbu et al.
Dalton transactions (Cambridge, England : 2003), 44(33), 14646-14655 (2015-07-28)
Copper(ii) and palladium(ii) meso-tetraferrocenylporphyrins ( and ) were employed as catalysts for electrochemical proton reduction in DMF using trifluoroacetic acid (TFA) or triethylamine hydrochloride (TEAHCl) as acids. Gas analysis under electrocatalytic conditions at a glassy carbon working electrode confirmed the...
Shuyou Chen et al.
Organic letters, 15(18), 4754-4757 (2013-09-10)
The Rh-catalyzed direct annulation of an aldehyde with an alkyne leading to indenone was achieved. The in situ temporal installation of acetylhydrazine enables the annulation of the ortho arene C-H bond with alkynes to form ketone hydrazone. Subsequently, the in...
Anna V Vologzhanina et al.
Inorganic chemistry, 54(12), 5827-5838 (2015-05-29)
Template condensation of dichloroglyoxime with n-hexadecylboronic acid on the corresponding metal ion as a matrix under vigorous reaction conditions afforded n-hexadecylboron-capped iron and cobalt(II) hexachloroclathrochelates. The complexes obtained were characterized using elemental analysis, MALDI-TOF mass spectrometry, IR, UV-vis, (1)H and...
Shengkun Li et al.
Organic letters, 15(5), 1036-1039 (2013-02-16)
A novel rhodium catalytic system with Naphos as ligand was developed for an efficient hydroaminomethylation of 1,1-diphenylethene under relatively mild conditions. This will allow for an atom-economic and environmentally benign synthesis of fenpiprane and related pharmaceuticals.
Yohan Lee et al.
Journal of nanoscience and nanotechnology, 13(11), 7477-7481 (2013-11-20)
In this work, rhodium nanoparticles were synthesized using hydrothermal method that is simple and easy to manipulate reaction and use nontoxic supercritical water. The rhodium nanoparticles were formed in uniform size and shape. These Rh NPs also acted as a...
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