29337-33-5Relevant academic research and scientific papers
A general synthetic method for the formation of substituted 5-aminotetrazoles from thioureas: a strategy for diversity amplification.
Batey,Powell
, p. 3237 - 3240 (2007/10/03)
A general method for the synthesis of 5-aminotetrazoles is outlined using the mercury(II)-promoted attack of azide anion on a thiourea. The reaction proceeds through a guanyl azide intermediate, which undergoes electrocyclization to the tetrazole. The method is high yielding and provides access to mono-, di-, and trisubstituted 5-aminotetrazoles, targets of potential interest for combinatorial library development.
Solid phase synthesis of oligomeric guanidiniums
Schneider, Stephen E.,Bishop, Patricia A.,Salazar, Mary Alice,Bishop, Owen A.,Anslyn, Eric V.
, p. 15063 - 15086 (2007/10/03)
Oligomers containing guanidinium linkages prepared via solid phase organic synthesis are of interest as possible therapeutic agents and in the assembly of supramolecular architectures. Efficient routes to these oligomers must be developed before their potential may be fully realized. Herein, four routes for their stepwise solid phase synthesis are described. In the first, a resin-bound thiourea was converted to a guanidinium using 2-chloro-1- methylpyridinium iodide. The second method utilized aza-Wittig couplings to prepare guanidiniums from resin-bound carbodiimides. Next, highly activated monomers prepared from bis-tert-butyloxycarbonythioureas and 2,4- dinitrofluorobenzene formed guanidiniums upon reaction with terminal amines. The optimum route, however, relied upon the 1-(3-dimethylaminopropyl)-3- ethylcarbodiimide hydrochloride promoted coupling of a protected thiourea monomer with a resin-bound amine to produce the guanidinium linkage. The thiourea monomers for this method are easily prepared from mono-protected diamines and benzoyl- or Fmoc-isothiocyanate. The procedure is straightforward, proceeds cleanly in a relatively short period of time, and is compatible with several functional groups.
Anchoring rhodium(I) on benzoylthiourea-functionalized silica xerogels. Production of recyclable hydroformylation catalysts and the crystal structure of the model compound
Cauzzi, Daniele,Lanfranchi, Maurizio,Marzolini, Giovanna,Predieri, Giovanni,Tiripicchio, Antonio,et al.
, p. 115 - 126 (2007/10/03)
The benzoylthiourea-functionalized silica xerogels, 4.5Si)2*SiO3/2(CH2)3NHC(S)NHC(O)Ph (XGbztu) and SiO3/2(CH2)3NHC(S)NHC(O)Ph (XGbztu*) have been prepared from (EtO)3Si(CH2)3NHC(S)NHC(O)Ph by the sol-gel process.They are able to bind rhodium(I) species giving the composite materials Rh/XGbztu and Rh/XGbztu*, which are very active insoluble and recoverable catalysts for the hydroformylation of styrene.The anchored species undergo major changes during the catalytic cycles, particularly in the Rh/XGbztu system, whose iso/normal selectivity ratio gradually increased in the first five runs.Furthermore, CH3(CH2)2NHC(S)NHC(O)Ph (HBztu) has been studied as a model of the surface binding function.The structure of , which represents a suitable molecular model for the anchored complexes, has been determined by X-ray diffraction. Keywords: Rhodium; Xerogel; Crystal structure; Hydroformylation; ESCA; Supported catalyst
METAL COMPLEXES TETHERED TO A FUNCTIONALIZED XEROGEL CONTAINING THE BENZOYLTHIOUREA MOIETY. CRYSTAL STRUCTURES OF trans- AND (Hbztu = N-BENZOYL-N'-PROPYLTHIOUREA)
Cauzzi, Daniele,Lanfranchi, Maurizio,Marzolini, Giovanna,Predieri, Giovanni,Tiripicchio, Antonio,Camellini, Marisa Tiripicchio
, p. 415 - 422 (2007/10/02)
The benzoylthiourea-functionalized xerogel XGbztu, obtained from (EtO)3Si(CH2)3NHC(S)NHC(O)Ph by hydrolysis and co-condensation with Si(EtO)4, is able to bind Pd(II) species by reaction with Pd(PhCN)2Cl2.The resulting system XGbztu/Pd is an active catalys
A Mild and Efficient Method for the Preparation of Guanidines
Poss, Michael A.,Iwanowicz, Edwin,Reid, Joyce A.,Lin, James,Gu, Zhengxiang
, p. 5933 - 5936 (2007/10/02)
A mild and efficient method for the preparation of guanidines by reaction of an acylated thiourea with an amine followed by removal of the acyl groups(s) from the intermediate acylguanidine is reported.Key Words: acylguanidine, acylthiourea, guanidine, water soluble carbodiimide
