Detail of "14319-64-3"

Reference

Coupling process

Coupling process. Martin, Michael K. (Shell Oil Co. , USA). U.S. US 4408017 A 4 Oct 1983, 6 pp. (English). (United States of America). CODEN: USXXAM. CLASS: IC: C08F008-00; C08F008-18; C08F297-04. NCL: 525288000. APPLICATION: US 82-382019 26 May 1982. DOCUMENT TYPE: Patent CA Section: 35 (Chemistry of Synthetic High Polymers) Li-terminated polymers of 31 C4-12 alkadienes and of 31 C8-18 monoalkenyl arenes are coupled by reaction with coupling agent I (n = 0-10; R = H, halogen, or C1-10 alkyl; R1 = halogen or C1-10 alkoxy; m = 0-2; p = 3 - m), e.g., bicycloheptenyl-2-trichlorosilane (I) [14319-64-3]. Incremental addn. of I to butadiene-capped polystyrene in the presence of Et2O [60-29-7] gave max. coupling yield and tricoupled efficiency.

Monolith- and silica-supported carboxylate-based Grubbs - Herrmann-type metathesis catalysts

Monolith- and silica-supported carboxylate-based Grubbs - Herrmann-type metathesis catalysts. Krause, Jens O.; Lubbad, Said; Nuyken, Oskar; Buchmeiser, Michael R. (Lehrstuhl fuer Makromolekulare Stoffe, Technische Universitaet Muenchen, Garching 85747, Germany). Advanced Synthesis & Catalysis, 345(8), 996-1004 (English) 2003 Wiley-VCH Verlag GmbH & Co. KGaA. CODEN: ASCAF7. ISSN: 1615-4150. DOCUMENT TYPE: Journal CA Section: 45 (Industrial Organic Chemicals, Leather, Fats, and Waxes) Section cross-reference(s): 29, 37, 67 The synthesis of silica- and monolith-supported Grubbs-Herrmann-type catalysts is described. Two polymerizable, carboxylate-contg. ligands, exo, exo-7-oxanorborn-2-ene-5,6-dicarboxylic anhydride and 7-oxanorborn-2-ene-5-carboxylic acid were surface-immobilized onto silica- and ring-opening metathesis (ROMP-) derived monolithic supports using "grafting-from" techniques. The "1st generation Grubbs catalyst", RuCl2(=CHPh)(PCy3)2, was used for these purposes. In addn., a poly(norborn-2-ene-b-exo, exo-norborn-2-ene-5,6-dicarboxylic anhydride) -coated silica 60 was prepd. The polymer supported anhydride and carboxylate groups were converted into the corresponding mono- and disilver salts, resp., and reacted with the Grubbs-Herrmann catalyst RuCl2(=CHPh)(IMesH2)(PCy3) [IMesH2 = 1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-ylidene]. Heterogenization was accomplished by exchange of one chlorine ligand with the polymeric, immobilized silver carboxylates to yield monolith-supported catalysts 4, 5, and 6 as well as silica-supported systems 7, 8 and 9. The actual compn. of these heterogenized catalysts was proven by the synthesis of a homogeneous analog, RuCl[7-oxanorbornan-2-(COOAg)-3-COO](=CHPh)(IMesH2)(PCy3) (3). All homogeneous and heterogeneous catalysts were used in ring-closing metathesis (RCM) of di-Et diallylmalonate, 1,7-octadiene, diallyldiphenylsilane, Me trans-3-pentenoate, diallyl ether, N,N-diallyltrifluoracetamide and t-Bu N,N-diallylcarbamate allowing turnover nos. (TON's) close to 1000. In a flow-through set-up, an auxiliary effect of pendant silver carboxylates was obsd. with catalyst 5, where the silver moiety functions as a (reversible) phosphine scavenger that both accelerates initiation and stabilizes the catalyst by preventing phosphine elution. Detailed catalytic studies were carried out with the monolith-supported systems 4 and 6 in order to investigate the effects of temp. 14319-64-3 and 650610-40-5 which are cas registry numbers of substances are two of reagents here. and chain-transfer agents (CTA's) such as cis-1,4-diacetoxybut-2-ene. In all RCM expts. Ru-leaching was low, resulting in a Ru-content of the RCM products ￡3.5 mg/g (3.5 ppm). .