5932-91-2Relevant academic research and scientific papers
Rhodium-catalysed hydroformylation of branched 1-alkenes; bulky phosphite vs. triphenylphosphine as modifying ligand
Van Rooy, Annemiek,De Bruijn, Jacques N. H.,Roobeek, Kees F.,Kamer, Paul C. J.,Van Leeuwen, Piet W. N. M.
, p. 69 - 73 (2007/10/03)
The influence of alkyl substituents in 1-alkene substrates in the rhodium-catalysed hydroformylation in the presence of tris(2-tertbutyl-4-methylphenyl) phosphite has been studied and compared with that observed for the reaction involving the conventional PPh3-modified catalyst. Hindered alkenes underwent hydroformylation at good rates (i.e. 1300 mol (mol Rh)-1 h-1 for 3,3-dimethyl-1-butene as T = 70°C and P = 20 bar (H2-CO)); under mild conditions the rates were only slightly affected by the alkyl substituents. The selectivity towards the linear aldehyde increases progressively with substitution, from 66% for 1-octene up to 100% for 3,3-dimethyl-1-butene, and the proportion of isomerized alkenes remained substantial (up to 17.4% for allylcyclohexane). The differences between the two systems are explained in terms of the different kinetics observed for them.
Heterocyclic pesticidal compounds
-
, (2008/06/13)
Compounds of the formula (I) STR1 which contain between 10 and 27 carbon atoms, and wherein m and n are independently selected from 0, 1 and 2; R2a is hydrogen, methyl, or ethyl; R2b is acetylene or contains between 3 and 18 carbon atoms and is a group R7, wherein R7 is a C1-13 non-aromatic hydrocarbyl group, optionally substituted by a cyano or C1-4 carbalkoxy group and/or by one or two hydroxy groups and/or by one to five halo atoms which are the same or different and/or by one to three groups R8 which are the same or different and each contain one to four hetero atoms, which are the same or different and are chosen from oxygen, sulphur, nitrogen and silicon, 1 to 10 carbon atoms and optionally 1 to 6 fluoro or chloro atoms or R2b is a 6-membered aromatic ring substituted by cyano and/or by one to three groups R8 and/or by a group --C CH, --C C-R7 or C C-halo and/or by one to five halo atoms and/or by one to three C1-4 haloalkyl groups wherein R7 and R8 are as hereinbefore defined; R4 and R6 are the same or different and are chosen from hydrogen, methyl, trifluoromethyl or cyano; and R5 is hydrogen or methyl provided that R2b is not propyl or butyl are described which have pesticidal activity, particularly against arthropod pests. Pesticidal formulations containing the compounds of the formula (I), their use in the control of pests and method for their preparation are also disclosed.
