111-70-6Relevant articles and documents
THE DIMESITYLBORON GROUP IN ORGANIC SYNTHESIS 2. THE C-ALKYLATION OF ALKYLDIMESITYLBORANES
Pelter, Andrew,Williams, Lorraine,Wilson, John W.
, p. 627 - 630 (1983)
It is demonstrated that anions α to the dimesitylboron group are alkylated at carbon in excellent yields.The alkylations may be repeated, so allowing for one-pot, one, two or three insertion reactions.
Hydrocarbonylation reactions using alkylphosphine-containing dendrimers based on a polyhedral oligosilsesquioxane core
Ropartz, Loic,Foster, Douglas F.,Morris, Russell E.,Slawin, Alexandra M. Z.,Cole-Hamilton, David J.
, p. 1997 - 2008 (2002)
Radical additions of HPR2 (R = Et, Cy) onto alkenyl groups or nucleophilic substitution reactions on chlorosilanes by LiCH2PR2 (R = Me, Hex) are used to prepare first and second-generation alkylphosphine-containing dendrimers based on a polyhedral oligomeric silsesquioxane (POSS) core. The first generation dendrimers (G1) are built on 16 or 24 arms, which are chlorides, vinyl groups or allyl moieties. Hydrosilylation (chlorosilane) followed by vinylation or allylation of octavinyl-functionalised POSS gave these G1 dendrimers. Successive hydrosilylation/allylation followed by hydrosilylation/vinylation produce the framework for the second-generation dendrimer (G2). The phosphorus-containing dendrimers are used as ligands for the hydrocarbonylation of alkenes (hex-1-ene, oct-1-ene, non-1-ene, prop-1-en-2-ol) in polar solvents (ethanol or THF) using the complexes [Rh(acac)(CO)2] or [Rh2(O2CMe)4] as metal source. Linear to branched ratios up to 3:1 for the alcohol products are obtained for the diethylphosphine dendrimers. The reactions were found to proceed mainly via the formation of the corresponding aldehydes.
Selective aldehyde reduction in ketoaldehydes with NaBH4-Na 2CO3-H2O at room temperatures
Chandrasekhar, Sosale,Shrinidhi, Annadka
, p. 2051 - 2056 (2014)
A variety of aliphatic and aromatic ketoaldehydes were reduced to the corresponding ketoalcohols with a mixture of sodium borohydride (1.2 equivalents) and sodium carbonate (sixfold molar excess) in water. Reactions were performed at room temperatures(typically) 2 h, and yields of isolated products generally ranged from 70% to 85%. A bis-carbonate-borane complex, [(BH3)2CO2]2- 2Na+, possibly formed from the reagent mixture, is likely the active reductant. The moderated reactivity of this acylborane species would explain the chemoselectivity observed in the reactions. The readily available reagents and the mild aqueous conditions make for ease of operation and environmental compatibility, and make a useful addition to available methodology. Copyright
Anomalous Rapid Reduction of Salicylaldehyde by Pyridine-Borane. Mechanism and Application to Selective Aldehyde Reduction
Chen, Joseph,Wayman, Kjirsten A.,Belshe, Marie A.,DiMare, Marcello
, p. 523 - 527 (1994)
The reduction of salicylaldehyde by pyridine-borane complex (PB) is much faster than that of other substituted benzaldehydes and ketones (seconds vs hours).Experiments reveal that this acceleration is due to an autocatalytic process involving a pyridinium boronate salt, a component of the equilibrating product mixture from PB reduction of salicylaldehyde.This pyridinium salt behaves as a mild Broensted acid and effectively accelerates aldehyde but not ketone reductions by PB.The observation that mild Broensted acids are catalysts for PB reductions led to the development of a method using AcOH in CH2Cl2 to promote the selective reduction of aldehydes in the presence of ketones.
Copper-Catalyzed Borylative Methylation of Alkyl Iodides with CO as the C1 Source: Advantaged by Faster Reaction of CuH over CuBpin
Wu, Fu-Peng,Wu, Xiao-Feng
, p. 11730 - 11734 (2021)
CuH and CuBpin are versatile catalysts and intermediates in organic chemistry. However, studies that involve both CuH and CuBpin in the same reaction is still rarely reported due to their high reactivity. Now, a study on CuH- and CuBpin-catalyzed borylative methylation of alkyl iodides with CO as the C1 source is reported. Various one carbon prolongated alkyl boranes (RCH2Bpin and RCH(Bpin)2) were produced in moderate to good yields from the corresponding alkyl iodides (RI). In this cooperative system, CuH reacts with alkyl iodide faster than CuBpin.
Kolbe Electrolysis of Biomass-Derived Fatty Acids Over Pt Nanocrystals in an Electrochemical Cell
Yuan, Gang,Wu, Chan,Zeng, Guorong,Niu, Xiaopo,Shen, Guoqiang,Wang, Li,Zhang, Xiangwen,Luque, Rafael,Wang, Qingfa
, p. 642 - 648 (2020)
Electrochemical valorization of non-food biomass-derived carboxylates into fuels is promising for the conversion, storage, and distribution of renewable electricity. Herein, we demonstrate that biofuels, hydrogen, and bicarbonate can be simultaneously produced in an electrochemical cell by one-step electrolysis of free fatty acids under ambient conditions on 3D self-supported ultralow Pt loading (2 wt %) electrode. The three valuable products can naturally separate from each other during the electrolysis in the alkaline aqueous solution. The experimental suggests that Pt(100) and Pt(110) are favorable for the production of non-Kolbe and Kolbe hydrocarbons, respectively. DFT calculation further clarifies the adsorption and stabilization of the reaction intermediates on Pt(100) and Pt(110).
Catalytic Reactions of Metalloporphyrins. 3. Catalytic Modification of Hydroboration-Oxidation of Olefin with Rhodium(III) Porphyrin as Catalyst
Aoyama, Yasuhiro,Tanaka, Yasutaka,Fujisawa, Takeshi,Watanabe, Takamichi,Toi, Hiroo,Ogoshi, Hisanobu
, p. 2555 - 2559 (1987)
(Octaethylporphyrinato)- or (tetraphenylporphyrinato)rhodium(III) chloride catalyzes the anti-Marcovnikov "hydration" of olefin with NaBH4 and O2 in THF. 1,5-Cyclooctadiene gives rise to cyclooctanol and 1,5-cyclooctanediol (in a ratio of approximately 1:2), and acetylenes are converted directly to alcohols under similar conditions.The initial step in the catalytic reaction of olefin is the hydride and borane transfers from BH4- respectively to RhIII porphyrin and olefin to give hydridorhodium (RhH) porphyrin and alkylborane.The RhH species undergoesoxidation with O2 back to RhIII with concomitant oxidation of alkylborane with retention of configuration.This coupled oxidation of alkylborane is in competition with its nonstereospecific autooxidation without assistance of Rh-H.The present system provides a catalytic modification of hydroboration-oxidation of olefin in the presence of oxygen, as illustrated by the one-pot conversion of 1-methylcyclohexene to (E)-2-methylcyclohexanol with 100 percent regioselectivity and up to 97 percent stereoselectivity.
BEHAVIOR OF AMINE IN RHODIUM COMPLEX-TERTIARY AMINE CATALYST SYSTEM ACTIVE FOR HYDROGENATION OF ALDEHYDE UNDER OXO REACTION CONDITIONS.
Mizoroki,Kioka,Suzuki,Sakatani,Okumura,Maruya
, p. 577 - 578 (1984)
The reaction was investigated to elucidate the reported disagreements on the kinetics. The concentration and the coordination stability of amine were found to affect the optimum pressure of carbon monoxide and the kinetics, and were suggested to control the reaction mechanism.
Highly efficient, general hydrogenation of aldehydes catalyzed by PNP iron pincer complexes
Zell, Thomas,Ben-David, Yehoshoa,Milstein, David
, p. 822 - 826 (2015)
A general protocol for the synthetically and industrially important hydrogenation of aldehydes to alcohols is reported. The reactions are catalyzed by well-defined iron pincer complexes that are capable of hydrogenation of aliphatic and aromatic aldehydes selectively and efficiently under mild conditions, with unprecedented turnover numbers.
Formate reduction of aldehydes using a photogenerated chromium carbonyl catalyst
Linn, D. E.,King, R. B.,King, A. D.
, p. C1 - C4 (1988)
The aldehydes RCHO (R = p-tolyl, p-anysil, n-hexyl) are reduced to the corresponding alcohols RCH2OH by sodium formate in 95percent aqueous methanol in the presence of a catalyst photogenerated from Cr(CO)6.