1122-69-6Relevant academic research and scientific papers
Silica-supported tripod triarylphosphane: Application to transition metal-catalyzed C(sp3)-H borylations
Iwai, Tomohiro,Murakami, Ryo,Harada, Tomoya,Kawamorita, Soichiro,Sawamura, Masaya
, p. 1563 - 1570 (2014)
A silica-supported tripod triarylphosphane (Silica-3p-TPP), containing a triphenylphosphane-type core tripodally immobilized on the silica surface, allows rhodium- and iridium-catalyzed C(sp3)-H borylations of amide, urea and alkylpyridine derivatives. The 31P CP/MAS NMR studies for the coordination behavior of the tripod phosphane towards a rhodium complex indicate efficient site isolation of the each phosphane center, allowing independent mono-P-coordination to the metal center.
Polymerization initiator, modified-conjugated diene polymer and tire prepared therefrom
-
, (2015/12/14)
The present disclosure relates to a polymerization initiator and a modified conjugated diene polymer prepared using the same, and more particularly to a polymerization initiator which is a compound represented by the following formula 1, and a modified conjugated diene polymer prepared using the same: wherein R1 to R5 are each independently hydrogen or a C1-10 alkyl group or its carbanion; n? represents the number of negative charges of the carbanion and is 1? to 5?; M is a metal; and n is equal to the number of carbanions in R1 to R5.
POLYMERIZATION INITIATOR, MODIFIED-CONJUGATED DIENE POLYMER AND TIRE PRODUCED THEREFROM
-
Page/Page column, (2014/06/24)
The present disclosure relates to a polymerization initiator and a modified conjugated diene polymer prepared using the same, and more particularly to a polymerization initiator which is a compound represented by the following formula 1, and a modified conjugated diene polymer prepared using the same: wherein R1 to R5 are each independently hydrogen or a C1-10 alkylgroup or its carbanion; n? represents the number of negative charges of the carbanion and is 1? to 5?; M is a metal; and n is equal to the number of carbanions in R1 to R5.
Yttrium-catalyzed addition of benzylic C-H bonds of alkyl pyridines to olefins
Guan, Bing-Tao,Wang, Baoli,Nishiura, Masayoshi,Hou, Zhaomin
supporting information, p. 4418 - 4421 (2013/05/21)
Cationic half-sandwich yttrium alkyl complexes catalyze the ortho-selective benzylic C-H addition of dialkyl pyridines to various olefins, such as ethylene, 1-hexene, styrenes, and 1,3-conjugated dienes, to afford new alkylated and allylated pyridine derivatives (see scheme; Cp=C5Me 5). A cationic half-sandwich yttrium picolyl species, such as [CpY(2-CH2-6-CH3C5H3N)] +, has been confirmed to be a key active species in this transformation. Copyright
Catalytic Reactions of Pyridines. V. Alkylation of α-, β-, and γ-Picolines with Alcohols catalyzed by Ammonium Halides
Kashiwagi, Hiroshi,Enomoto, Saburo
, p. 2213 - 2218 (2007/10/02)
A new method was found for the homogeneous liquid-phase alkylation of α-, β-, and γ-picolines with either methanol or ethanol.Addition of a catalytic amount of an ammonium halide to a mixture of a picoline and an alcohol resulted in a great increase in the yields of both side-chain and α-alkylated derivatives of the starting picoline when the reaction was carried out at 320-335 deg C in an atmosphere of nitrogen.The higher the reaction temperature, the greater the yields of side-chain alkylated derivatives became.In practice, this alkylation gave 2-ethylpyridine, and 2,6-lutidine from α-picoline with methanol, 3-ethylpyridine and 2,5-lutidine from β-picoline from methanol, 4-ethylpyridine and 2,4-lutidine from γ-picoline with methanol, 2-propylpyridine and 2-ethyl-6-methylpyridine from α-picoline with ethanol, 2-ethyl-5-methylpyridine from β-picoline with ethanol, and 4-propylpyridine and 2-ethyl-4-methylpyridine from γ-picoline with ethanol.Keywords-alkylation; catalyst; ammonium halide; α-picoline; β-picoline; γ-picoline; ethylpyridine; propylpyridine; methanol; ethanol
