Home About us Contact
|
Home About us Contact | ||
|
|
||
Divergent Synthesis (divergent + synthesis)
Selected AbstractsConvergent/Divergent Synthesis and Photophysical Studies of Alternating Benzene,Furan Oligoaryls from Substituted Propargylic DithioacetalsCHEMISTRY - AN ASIAN JOURNAL, Issue 1-2 2006Chih-Ming Chou Abstract A range of oligoaryls that contain alternating benzene,furan rings is synthesized by a rapid convergent/divergent method from the annulation of a propargylic dithioacetal and an aldehyde with a propargylic dithioacetal moiety as a substituent. These oligomers are fairly soluble in a range of organic solvents and can be easily purified by reprecipitation. The substituents on the furan rings can be varied according to the substituents in the starting propargylic dithioacetals. This route provides a useful procedure for the synthesis of alternating benzene,furan oligomers without repeated units. These furan-containing oligoaryls are highly fluorescent in the visible region and are electrochemically active. The band gaps of these oligomers appear to be less sensitive towards changes in conjugation length than those of oligofurans. [source] ChemInform Abstract: A Divergent Synthesis of Substituted 2-Aminoimidazoles from 2-Aminopyrimidines.CHEMINFORM, Issue 3 2009Denis S. Ermolat'ev 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] Divergent Synthesis of Two Precursors of 3,-Homo-2,-deoxy- and 2,-Homo-3,-deoxy-carbocyclic Nucleosides.CHEMINFORM, Issue 7 2003Jose M. Blanco Abstract For Abstract see ChemInform Abstract in Full Text. [source] Divergent synthesis of dendrimer-like macromolecules through a combination of atom transfer radical polymerization and click reactionJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 15 2007Qingchun Liu Abstract This article describes a divergent strategy to prepare dendrimer-like macromolecules from vinyl monomers through a combination of atom transfer radical polymerization (ATRP) and click reaction. Firstly, star-shaped polystyrene (PS) with three arms was prepared through ATRP of styrene starting from a three-arm initiator. Next, the terminal bromides of the star-shaped PS were substituted with azido groups. Afterwards, the azido-terminated star-shaped PS was reacted with propargyl 2,2-bis((2,-bromo-2,-methylpropanoyloxy)methyl)propionate (PBMP) via click reaction. Star-shaped PS with six terminal bromide groups was afforded and served as the initiator for the polymerization of styrene to afford the second-generation dendrimer-like PS. Iterative process of the aforementioned sequence of reactions could allow the preparation of the third-generation dendrimer-like PS. When the second-generation dendrimer-like PS with 12 bromide groups used as an initiator for the polymerization of tert -butyl acrylate, the third-generation dendrimer-like block copolymer with a PS core and a poly (tert -butyl acrylate) (PtBA) corona was afforded. Subsequently PtBA segments were selectively hydrolyzed with hydrochloric acid, resulting an amphiphilic branched copolymer with inner dendritic PS and outer linear poly(acrylic acid) (PAA). Following the same polymerization procedures, the dendrimer-like PS and PS- block -PtBA copolymers of second generation originating from six-arm initiator were also synthesized. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3330,3341, 2007 [source] Practical syntheses of [1,3,5]-triazine dendritic molecules on solid supportsJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 7 2006Suzanne J. Dilly Abstract A practical and divergent synthesis of supported [1,3,5]-triazine dendritic molecules on Wang resin, PEGA resin, SynPhaseÔ Lanterns, and silica gel is described. The alkylamine linkers used allow derivatization with functionality for both synthetic (e.g., supported reagent and scavenger activity) and chemical biology applications. The use of supported intermediates allows differentiation of symmetric linkers without the need for protecting group chemistry. The synthetic route uses inexpensive, readily available starting materials in a straightforward and scaleable strategy. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2248,2259, 2006 [source] Accelerated iterative strategy for the divergent synthesis of dendritic macromolecules using a combination of living radical polymerization and an irreversible terminator multifunctional initiatorJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 20 2005Virgil Percec Abstract Our laboratory has reported the elaboration of an iterative strategy for the synthesis of dendritic macromolecules from conventional monomers. This synthetic method involves a combination of self-regulated metal-catalyzed living radical polymerization initiated from arenesulfonyl chlorides and an irreversible terminator multifunctional initiator (TERMINI). The previous TERMINI, (1,1-dimethylethyl)[[1-[3,5-bis(S -phenyl-4- N,N, diethylthiocarbamate)phenyl]ethenyl]oxy]dimethylsilane, was prepared in nine reaction steps. The replacement of the previous TERMINI with one that requires only three steps for its synthesis, diethylthiocarbamic acid S -{3-[1-(tert -butyl-dimethyl-silanyloxy)-vinyl]-5-diethylcarbamoylsulfanyl-phenyl} ester, and the use of the more reactive Cu2S/2,2,-bipyridine rather than the Cu2O/2,2,-bipyridine self-regulated catalyst have generated an accelerated method for the synthesis of dendritic macromolecules. This method provides rational design strategies for the synthesis of dendritic macromolecules with different compaction by the use of a single monomer. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4894,4906, 2005 [source] | ||||||||||