64181-30-2Relevant academic research and scientific papers
Cobalt-Catalyzed Csp3-Csp3 Cross-Coupling of Functionalized Alkylzinc Reagents with Alkyl Iodides
Lutter, Ferdinand H.,Grokenberger, Lucie,Benz, Maximilian,Knochel, Paul
supporting information, p. 3028 - 3032 (2020/04/10)
A mild cobalt-catalyzed Negishi-type cross-coupling of various functionalized dialkylzinc reagents with primary and secondary alkyl iodides in acetonitrile is reported using a combination of 20% CoCl2 and chelating nitrogen ligands. The method allows the construction of molecules with alkyl chains bearing sensitive functional groups at room temperature.
Nickel-Catalyzed Kumada Coupling of Benzyl Chlorides and Vinylogous Derivatives
Soler-Yanes, Rita,Guisán-Ceinos, Manuel,Bu?uel, Elena,Cárdenas, Diego J.
supporting information, p. 6625 - 6629 (2016/02/19)
Conditions for the fast Ni-catalyzed Kumada-type cross-coupling of functionalized benzyl and allyl chlorides with alkylmagnesium reagents were discovered. The use of Ni(acac)2-TMEDA (acac = acetylacetonate, TMEDA = N,N,N′,N′-tetramethyl-1,2-ethylenediamine) allows the presence of reactive functional groups on the electrophile. On the other hand, the use of diallyl ether was shown to provide fast coupling at low temperature with a low catalyst loading. The reaction seems to follow a radical pathway.
(Dialkoxymethyl)lithiums: Generation, Stability, and Synthetic Transformations
Shiner, Christopher S.,Tsunoda, Tetsuto,Goodman, Burton A.,Ingham, Stephen,Lee, Shi-hung,Vorndam, Paul E.
, p. 1381 - 1392 (2007/10/02)
(Dialkoxymethyl)lithium reagents, (RO)2CHLi, can be generated simply and efficiently and employed as synthetically useful one-carbon nucleophiles.Reductive lithiation of phenylthio-substituted precursors, (RO)2CHSPh, at -95 deg C or transmetalation of tri-n-butylstannyl compounds, (RO)2CHSn(n-Bu)3, at -110 to -111 deg C afforded the acyclic species (MeO)2CHLi (4) and (EtO)2CHLi (5).The cyclic reagents, 2-lithio-1,3-dioxolane (6) and 2-lithio-1,3-dioxane (7), were similarly prepared at -78 deg C by reductive lithiation or transmetalation.Reactions of(dialkoxymethyl)lithiums with electrophiles, including aldehydes, ketones, 2-cyclohexen-1-one (1,2- or 1,4-addition as desired), dimethyl sulfate, primary alkyl bromides, epoxides, oxetane, and n-Bu3SnCl, afforded structurally diverse, functionalized acetals.In these experiments, which emphasized transformations of lithiodioxane 7, yields of products generally exceeded 90percent.The thermal stability of each reagent was investigated at several temperatures.The acyclic compounds 4 and 5 decompose rapidly even at -95 deg C, whereas lithiodioxolane 6 and dioxane derivative 7 are relatively stable at -78 and -45 deg C, respectively.These striking differences in solution lifetimes can be rationalized in terms of alternative decomposition pathways and steric and stereoelectronic factors.The primary products of thermal decomposition of 7 can be ascribed to formation of a reactive carbene or carbenoid via α-elimination.Equilibration experiments established that (dialkoxymethyl)lithium 7 is more stable thermodynamically than the α-monoalkoxy species lithium, in accord with previous ab initio calculations.
