- Neutral Fe(iv) alkylidenes, including some that bind dinitrogen
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Neutral, formally Fe(iv) alkylidene species are sought as plausible olefin metathesis catalysts, and the synthesis of several is described herein. The complexes are prepared via nucleophilic attack (Nu = MeLi, PhCH2K, 2-picolyllithium, Me2PCH2Li, MePhPCH2Li, Ph2PCH2Li) at the imine of cationic [mer-{κ-C,N,C-(C6H4-yl)-2-CH=N(2-C6H4-C(iPr)=)}Fe(PMe3)3][B(3,5-CF3-C6H3)4]. In contrast, MeMgCl and mesityllithium displaced and deprotonated bound PMe3, respectively. Structural details are provided for mer-{κ-C,N,C-(C6H4-yl)-2-CH(Bn)N(2-C6H4-C(iPr)=)}Fe{trans-(PMe3)2}N2 and {κ-C,N,C,P-(C6H4-yl)-2-CH(CH2PMe2)N(2-C6H4-C(iPr)=)}Fe(PMe3)2.
- Lindley, Brian M.,Jacobs, Brian P.,MacMillan, Samantha N.,Wolczanski, Peter T.
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- A DNMR Study of Restricted Methylene Rotation in 2-Pyridylmethyl- and 3-Methyl-2-pyridylmethyllithium
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Thermodynamical parameters for the restricted rotation of the title carbanions have been obtained by means of the DNMR techniques.The activation energies and entropies thus obtained are about 93 kJ mol-1 and 95 J K-1 mol-1 for the two carbanions studied; these values are larger than those of the similar rotations observed in arylmethanide ions.The methylene rotation is thus extremely hindered in these carbanions.
- Matsui, Hideki,Yoshino, Akihiro,Yoshida, Tadayoshi,Takahashi, Kensuke
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- Complexation behaviour of LiCl and LiPF6-model studies in the solid-state and in solution using a bidentate picolyl-based ligand
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Structural knowledge on ubiquitous lithium salts in solution and in the crystalline state is of paramount importance for our understanding of many chemical reactions and of the electrolyte behaviour in lithium ion batteries. A bulky bidentate Si-based ligand (6) was used to create simplified model systems suitable for correlating structures of LiCl and LiPF6 complexes in the solid-state and in solution by combining various experimental, spectroscopic, and computational methods. Solution studies were performed using 1H DOSY, multinuclear variable temperature NMR spectroscopy, and quantum chemical calculations. [Ph2Si(2-CH2Py)2·LiCl]2 (3) dissociates into a monomeric species (9) in THF. For [Ph2Si(2-CH2Py)2·LiPF6]2 (11), low temperature NMR studies revealed an unprecedented chiral coordination mode (12) in non-coordinating solvents. This journal is
- Espinosa-Jalapa, Noel Angel,Berg, Nele,Seidl, Michael,Shenderovich, Ilya G.,Gschwind, Ruth M.,Bauer, Jonathan O.
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- REACTION OF 2-PICOLYLLITHIUM AND 6-METHYL-2-PICOLYLLITHIUM WITH VINYL(tert-BUTYL)ACETYLENE
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The possibility of obtaining pyridylallene hydrocarbons with normal structure with a branched grouping in the side chain on the basis of vinyl(alkyl)acetylene hydrocarbons with iso structures and, respectively, 2-picolyl and 2,6-lutidyllithium is demonstrated.
- Cherkasov, L. N.
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- Synthesis, structure and coordination of the ambiphilic ligand (2-picolyl)BCy2
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The new pyridine-borane compound (2-picolyl)BCy2, readily prepared from 2-picolyllithium and ClBCy2, adopts a head-to-tail dimeric structure in the solid state as indicated by X-ray diffraction analysis and according to NMR and DFT studies, the dimeric form equilibrates in solution with a strained monomeric structure; the ambiphilic behavior of the new compound is illustrated by its bridging coordination to the (p-cymene)RuCl2 unit. The Royal Society of Chemistry.
- Vergnaud, Jerome,Ayed, Tahra,Hussein, Khansaa,Vendier, Laure,Grellier, Mary,Bouhadir, Ghenwa,Barthelat, Jean-Claude,Sabo-Etienne, Sylviane,Bourissou, Didier
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p. 2370 - 2372
(2008/02/04)
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- Carbon-linked substituted piperidines and derivatives thereof useful as histamine H3 antagonists
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Disclosed are compounds of the formula or a pharmaceutically acceptable salt thereof, wherein: M1 and M3 are CH or N; M2 is CH, CF or N; Y is —C(═O)—, —C(═S)—, —(CH2)q—, —C(═NOR7)— or —SO1-2—; Z is a bond or optionally substituted alkylene or alkenylene; R1 is H, alkyl, alkenyl, or optionally substituted cycloalkyl, aryl, heteroaryl, heterocycloalkyl or a group of the formula: where ring A is a monoheteroaryl ring; R1 is optionally substituted alkyl, alkenyl, aryl, heteroaryl, cycloalkyl or heterocycloalkyl; and the remaining variables are as defined in the specification; compositions and methods of treating allergy-induced airway responses, congestion, obesity, metabolic syndrome nonalcoholic fatty liver disease, hepatic steatosis, nonalcoholic steatohepatitis, cirrhosis, hepatacellular carcinoma or cognition deficit disorders using said compounds, alone or in combination with other agents.
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Page/Page column 28-29
(2008/06/13)
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- Efficient routes to acenaphthylene-fused polycyclic arenes/heteroarenes and heterocyclic fluoranthene analogues
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The acenaphthenone-derived a-oxoketene dithioacetal 2 has been subjected to various [3 + 3] aromatic and heteroaromatic annulation and other heterocyclization reactions previously developed in our laboratory, providing short and efficient routes to a diverse range of known and unknown acenaphtho-annulated linear and angular PAHs, heteroaromatics and five-membered heterocycles in good yields. Thus, benzo- and naphthoannulation of 2 with various allyl and benzyl Grignard reagents afforded substituted fluoranthenes 4a-c and benzo[k]fluoranthene 8, respectively, in good yields. Similarly, the parent benzo[j]fluoranthene 15a and its substituted derivative 16b have been synthesized by base-induced conjugate 1,4-addition of arylacetonitriles to 2, followed by acid-induced cyclization of the conjugate adducts 12a-b to give 13a-b and subsequent further transformations. The adducts obtained by 1,4-addition of anions derived from acetophenone and acenaphthenone were subjected to heterocyclization in the presence of ammonium acetate to give 8-arylacenaphtho[1,2-b]pyridines 18a-b and bis(acenaphtho)-annulated pyridine 20. Heterocyclization of 2 with bifunctional nucleophiles such as 2-picolyllithium and guanidinium nitrate afforded the corresponding acenaphtho[1,2-b]quinolizinium salt 23 and acenaphtho[1,2-d]pyrimidine 24, respectively, in high yields. Finally, acenaphtho[1,2-c]-fused five-membered heterocycles such as 7-(methylthio)acenaphtho[1,2-c]thiophene (25), 7-(methylthio)acenaphtho[1,2-c]furan (27) and 7-(methylthio)acenaphtho[1,2-c] pyrrole-2-carboxylic acid (30) were obtained in good yields by subjection of 2 to Simmons-Smith reaction conditions or by treatment with dimethylsulfonium methylide or glycinate dianion. Some of these newly synthesized PAHs or fused heterocycles were subjected to Raney Ni desulfurization to furnish sulfurfree compounds. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005.
- Panda, Kausik,Venkatesh, Chelvam,Ila, Hiriyakkanavar,Junjappa, Hiriyakkanavar
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p. 2045 - 2055
(2007/10/03)
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- CHEMICAL COMPOUNDS
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Compounds of formula (I):wherein variable groups are as defined within; for use in the inhibition of 11betaHSD1 are described
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- 4-(ARYL OR HETEROARYL) -2-BUTYLAMINE DERIVATIVES AND THEIR USE AS GLUCOCORTICOID LIGANS
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A compound of Formula (IA) or Formula (IB) wherein R1, R2, R3, R4, R5, R6, R7 and R8 are as defined herein, or a tautomer, prodrug, solvate, or salt thereof; pharmaceutical compositions containing such compounds, and methods of modulating the glucocorticoid receptor function and methods of treating disease-states or conditions mediated by the glucocorticoid receptor function or characterized by inflammatory, allergic, or proliferative processes in a patient using these compounds.
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