5223-59-6Relevant academic research and scientific papers
Dual Rh?Ru Catalysts for Reductive Hydroformylation of Olefins to Alcohols
Rodrigues, Fábio M. S.,Kucmierczyk, Peter K.,Pineiro, Marta,Jackstell, Ralf,Franke, Robert,Pereira, Mariette M.,Beller, Matthias
, p. 2310 - 2314 (2018/07/31)
An active and selective dual catalytic system to promote domino hydroformylation–reduction reactions is described. Apart from terminal, di- and trisubstituted olefins, for the first time the less active internal C?C double bond of tetrasubstituted alkenes can also be utilized. As an example, 2,3-dimethylbut-2-ene is converted into the corresponding n-alcohol with high yield (90 %) as well as regio- and chemoselectivity (>97 %). Key for this development is the use of a combination of Rh complexes with bulky monophosphite ligands and the Ru-based Shvo's complex. A variety of aromatic and aliphatic alkenes can be directly used to obtain mainly linear alcohols.
Cross-coupling of nonactivated primary and secondary alkyl halides with aryl Grignard reagents catalyzed by chiral iron pincer complexes
Bauer, Gerald,Cheung, Chi Wai,Hu, Xile
, p. 1726 - 1732 (2015/06/16)
Iron(III) bisoxazolinylphenylamido (bopa) pincer complexes are efficient precatalysts for the cross-coupling of nonactivated primary and secondary alkyl halides with phenyl Grignard reagents. The reactions proceed at room temperature in moderate to excellent yields. A variety of functional groups can be tolerated. The enantioselectivity of the coupling of secondary alkyl halides is low.
Templation of the excited-state chemistry of α-(n-alkyl) dibenzyl ketones: how guest packing within a nanoscale supramolecular capsule influences photochemistry
Gibb, Corinne L. D.,Sundaresan, Arun Kumar,Ramamurthy,Gibb, Bruce C.
, p. 4069 - 4080 (2008/12/20)
Excited-state behavior of eight α-alkyl dibenzyl ketones (alkyl = CH3 through n-C8H17) that are capable of undergoing type II and/or type I photoreactions has been explored in isotropic solution and within a water-soluble capsule. The study consisted of two parts: photochemistry that explored the excited-state chemistry and an NMR analysis that revealed the packing of each guest within the capsule. The NMR data (COSY, NOESY, and TOCSY experiments) revealed that ternary complexes between α-alkyl dibenzyl ketones and the capsule formed by two cavitands are kinetically stable, and the guests fall into three packing motifs modulated by the length of the α-alkyl chain. In essence, the host is acting as an external template to promote the formation of distinct guest conformers. The major products from all eight guests upon irradiation either in hexane or in buffer solution resulted from the well-known Norrish type I reaction. However, within the capsule the excited-state chemistry of the eight ketones was dependent on the alkyl chain length. The first group consisted of α-hexyl, α-heptyl, and α-octyl dibenzyl ketones that yielded large amounts of Norrish type II products within the host, while in solution the major products were from Norrish type I reaction. The second group consists of α-butyl and α-pentyl dibenzyl ketones that yield equimolar amounts of two rearranged starting ketones within the capsule (combined yield of ca 60%), while in solution no such products were formed. The third group consisted of α-methyl, α-ethyl, and α-propyl dibenzyl ketones that within the capsule yielded only one (not two) rearranged starting ketone in larger amounts (21-35%) while in solution no rearrangement product was obtained. Variation in the photochemistry of the guest within the capsule, with respect to the α-alkyl chain length of the guest, highlights the importance of how a small variation in supramolecular structure can influence the selectivity within a confined nanoscale reactor.
Pd-catalyzed cleavage of benzylic nitro bonds: New opportunities for asymmetric synthesis
Fessard, Thomas C.,Motoyoshi, Hajime,Carreira, Erick M.
, p. 2078 - 2081 (2008/02/13)
Without a trace: Benzylic nitroalkanes are reduced to the corresponding parent alkanes in good yields by using a simple procedure involving heterolytic C-N bond cleavage (see scheme). Traceless removal of the nitro group leaves behind a stereogenic center that may otherwise be difficult to install. This reaction significantly expands the scope of building blocks that can be accessed. (Chemical Equation Presented)
The reaction of benzotrihalides and benzal halides with magnesium. Synthetic and mechanistic studies
Ashby, E. C.,Al-Fekri, Dheya M.
, p. 275 - 292 (2007/10/02)
The benzotrihalides (PhCX3) where X = Cl, Br, and F were allowed to react with magnesium in THF at room temperature.When the halide was chloride or bromide, the trihalide gave diphenylacetylene in high yield in addition to several minor products which were identified.No reaction was observed when the halide was fluoride.When the corresponding dichloride was allowed to react with magnesium in THF, stilbene was formed as the major product.The possible mechanisms for these reactions are discussed.
REACTION OF DITHIOCARBOXYLIC ESTERS WITH DIMETHYL ACETYLENEDICARBOXYLATE
Drozd, V. N.,Popova, O. A.
, p. 1741 - 1747 (2007/10/02)
It was shown that substituted allyl, benzyl, and propargyl esters of dithiocarboxylic acids react with dimethyl acetylenedicarboxylate by a cycloaddition mechanism with a simultaneous - or -sigmatropic shift to form 2,2-substituted 4,5-dimethoxycarbonyl-1,3-dithioles.
