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Selected AbstractsNew Access to Homodinuclear Half-Sandwich Vinylidenemanganese ComplexesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 5 2005Koushik Venkatesan Abstract The d6 low-spin MnI half-sandwich dinuclear complexes of the type [{Mn(MeC5H4)(R2PCH2CH2PR2)=C=C(SnMe3)}2{X}] (X = {,-1,4-C6H4}, R = Me, 2a; X = {,-1,4-C6H4}, R = Et, 2b; X = {,-1,3-C6H4}, R = Me, 3a; X = {,-1,3-C6H4}, R = Et, 3b; X = {,-4,4-C6H4 -C6H4}, R = Me, 4a; X = {,-4,4-C6H4 -C6H4}, R = Et, 4b; X = {,-1,4-C4H2S}, R = Me, 5a; X = {,-1,4-C4H2S}, R = Et, 5b) were obtained by the treatment of [Mn(C5H4Me)(,6 -cycloheptatriene)] with 0.5 equiv. of the corresponding acetylene Me3Sn,C,C,X,C,C,SnMe3 (X = {,-1,4-C6H4}, {,-1,3-C6H4}, {,-4,4-C6H4 -C6H4}, {,-1,4-C4H2S}) and R2PCH2CH2PR2 (R = Me, Et) at 50 °C for 12 h to yield the corresponding dinuclear complexes in very good yields. These dinuclear tin-substituted vinylidene complexes were further treated with an excess of MeOH to give the corresponding dinuclear parent vinylidene complexes of the type [{Mn(MeC5H4)(R2PCH2CH2PR2)=C=C(H)}2{X}] (X = {,-1,4-C6H4}, R = Me, 6a; X = {,-1,4-C6H4}, R = Et, 6b; X = {,-1,3-C6H4}, R = Me, 7a; X = {,-1,3-C6H4}, R = Et, 7b; X = {,-4,4-C6H4 -C6H4}, R = Me, 8a; X = {,-4,4-C6H4 -C6H4}, R = Et, 8b). All dinuclear compounds were characterised by NMR and IR spectroscopy and elemental analysis. X-ray diffraction studies were performed on complexes 2b, 3a, 4a and 6a. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] N-Heterocyclic Carbene-Mediated Organocatalytic Transfer of Tin onto Aldehydes: New Access to ,-Silyloxyalkylstannanes and ,-SilyloxyallylstannanesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 4 2010Romain Blanc Abstract A new, highly efficient and mild N-heterocyclic carbene (NHC)-mediated organocatalytic procedure for the transfer of tin from tributyl(trimethylsilyl)stannane (Bu3SnSiMe3) onto aldehydes for the preparation of ,-silyloxyalkylstannanes and ,-silyloxyallylstannanes has been developed. [source] ChemInform Abstract: Metal-Catalyzed Rearrangement of Enantiomerically Pure Alkylidenecyclopropane Derivatives as a New Access to Cyclobutenes Possessing Quaternary Stereocenters.CHEMINFORM, Issue 6 2010Ahmad Masarwa Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: One-Pot Multicomponent Synthesis of 2,3-Dihydropyrans: New Access to Furanose,Pyranose 1,3-C-C-Linked-Disaccharides.CHEMINFORM, Issue 29 2009Daniele Castagnolo Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Mild and Stereoselective Friedel,Crafts Alkylation of Phenol Derivatives with Vinyloxiranes: A New Access to Cycloalkenobenzofurans.CHEMINFORM, Issue 16 2008Ferruccio Bertolini Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: New Access to H-Phosphonates via Metal-Catalyzed Phosphorus,Oxygen Bond Formation.CHEMINFORM, Issue 1 2008Laetitia Coudray Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] A Highly Selective Ir-Catalyzed Borylation of 2-Substituted Indoles: A New Access to 2,7- and 2,4,7-Substituted Indoles.CHEMINFORM, Issue 16 2007Wei Fun Lo Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Cyclic and Acyclic Sulfonimides in Reactions with Rh(II)-Ketocarbenoids: A New Access to Chemoselective O-Functionalization of the Imidic Carbonyl Groups.CHEMINFORM, Issue 11 2006Vsevolod Nikolaev Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] New Access to Pyrazole, Oxa(thia)diazole and Oxadiazine Derivatives.CHEMINFORM, Issue 22 2005Alaa A. Hassan Abstract For Abstract see ChemInform Abstract in Full Text. [source] Regioselective Hydroaminomethylation of 1,1-Diaryl-allyl-alcohols: A New Access to 4,4-Diarylbutylamines.CHEMINFORM, Issue 14 2005Andreas Schmidt No abstract is available for this article. [source] New Access to 1,3-Diketones from Aldehydes.CHEMINFORM, Issue 9 2005Valerie Fargeas Abstract For Abstract see ChemInform Abstract in Full Text. [source] ChemInform Abstract: Sequencing Pericyclic Reactions: The Ester Dienolate [2,3]-Wittig/Oxy-Cope Rearrangement/Carbonyl Ene Reaction, a New Access to Substituted Carbocycles.CHEMINFORM, Issue 11 2002Martin Hiersemann Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] New access to pyrazole, oxa(thia)diazole and oxadiazine derivativesHETEROATOM CHEMISTRY, Issue 1 2005Alaa A. Hassan 1,4-Disubstituted thiosemicarbazides 1b,f reacted with ethenetetracarbonitrile (5) in di- methylformamide with formation of 2-substituted 5-phenyl-1,3,4-thiadiazoles 2a,f and 2-substituted 5-phenyl-1,3,4-oxadiazoles 4a,f. Upon addition of 5 to 1c,e in chlorobenzene, 3-amino-2-benzoyl-4,5,5-tri- cyano-2,5-dihydro-1H -pyrazole-1-[N -(4-tricyanovi-nyl)phenyl]carbothioamide (12), 5-benzylamino-, and 5-allylamino-4-benzoyl-2,3-dihydro-[1,3,4]thiadiazol- 2,2-dicarbonitrile (13a,b) and 5-amino-1-benzoylpyrazole-3,4-dicarbonitrile (14) as well as 2-phenyl- 4H -[1,3,4]-oxadiazine-5,6-dicarbonitrile (15) were formed. Rationales for the role of the solvent and the conversions observed are presented. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:12,19, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20071 [source] New access to thiazolo[4,5- d]pyrimidine derivativessJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 5 2006M. Bakavoli 4-Amino-5-bromo-2-substituted-aminopyrimidines are readily obtained from the newly prepared 5-bromo-2,4-dichloro-6-methylpyrimidine by sequential treatment with ethanolic ammonia and secondary amines. These compounds were successfully reacted with various isothiocyanates in the presence of sodamide in DMF to form the new thiazolo[4,5- d] pyrimidine derivatives. [source] Synthesis of 5-phenyl-5,6,7,8-tetrahydro-1,6-naphthyridines and 5-phenyl-6,7,8,9-tetrahydro-5H -pyrido[3,2- c]azepines as potential D1 receptor ligandsJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 6 2004Thomas Hussenether A new access to 5-phenyl-5,6,7,8-tetrahydro-1,6-naphthyridines 25a-28a (n=1) and 5-phenyl-6,7,8,9-tetrahydro-5H -pyrido[3,2- c]azepines 25b-28b (n=2) has been developed by first preparing the functional pyridine moiety followed by intramolecular cyclization forming the partially reduced ring. [source] Synthesis of Tricyclic Fused 3-Aminopyridines through Intramolecular CoI -Catalyzed [2+2+2] Cycloaddition between Ynamides, Nitriles, and AlkynesCHEMISTRY - A EUROPEAN JOURNAL, Issue 9 2009Pierre Garcia Abstract Three-ring circus: An expedient route to tricyclic fused 2-trimethylsilyl-3-aminopyridines exhibiting unprecedented skeletons is described. The key step is a very efficient cobalt-catalyzed [2+2+2] cycloaddition of a polyunsaturated compound displaying an ynamide, an alkyne, and a nitrile functionality (see picture). The first [2+2+2] cocyclizations between ynamides, nitriles, and alkynes are reported. They open a new access to unprecedented nitrogen-containing heterocycles of type 2-trimethylsilyl-3-aminopyridines. Such frameworks, which can be found in various compounds of biological interest, are very difficult to prepare by conventional methods. However, using [CpCo(C2H4)2] (Cp=cyclopentadienyl) as catalyst, the intramolecular cyclizations could be achieved in up to 100,% yield. The presence of the trimethylsilyl group allowed a rare type of Hiyama cross-coupling: one of the silylated pyridines could be coupled with p -iodoanisole to give a new type of biaryl system. [source] | ||||||||||