Copper(<scp>i</scp>)-catalysed transfer hydrogenations with ammonia borane
作者:Eva Korytiaková、Niklas O. Thiel、Felix Pape、Johannes F. Teichert
DOI:10.1039/c6cc09067b
日期:——
Highly Z-selective alkyne transfer semihydrogenations and conjugate transferhydrogenations of enoates can be effected by employing a readily available copper(I)/N-heterocyclic carbene (NHC) complex, [IPrCuOH], in combination with ammoniaborane as a H2 equivalent.
The One-Pot Wittig Reaction: A Facile Synthesis of α,β-Unsaturated Esters and Nitriles by Using Nanocrystalline Magnesium Oxide
作者:Boyapati M. Choudary、Koosam Mahendar、M. Lakshmi Kantam、Kalluri V. S. Ranganath、Taimur Athar
DOI:10.1002/adsc.200606001
日期:2006.9
Nanocrystalline magnesium oxide was found to be an effective heterogeneous, solid base catalyst for the one-pot Wittig reaction to afford α,β-unsaturatedesters and nitriles in excellent yields with high E-stereoselectivity in the presence of triphenylphosphine under mild conditions.
We identified 2-phenylisophosphindoline 2-oxide as a suitable and potentially tunable catalyst for the catalytic Wittigreaction of aldehydes with activated organohalides. This catalyst was obtained by a straightforward two-step synthesis. Trimethoxysilane proved to be an efficient reducing agent for the in situ generation and regeneration of the catalyst from the corresponding phosphane oxide. Sodium
A Palladium Nanoparticle-Nanomicelle Combination for the Stereoselective Semihydrogenation of Alkynes in Water at Room Temperature
作者:Eric D. Slack、Christopher M. Gabriel、Bruce H. Lipshutz
DOI:10.1002/anie.201407723
日期:2014.12.15
The addition of NaBH4 to Pd(OAc)2 in water containing nanomicelles leads to the generation of H2 and Pd nanoparticles. Subsequent reduction of disubstituted alkynes affords Z‐alkenes in high yields. These reactions are general, take place in water at ambient temperatures, and offer recycling of the aqueous reaction mixture along with low overall E Factors.
在含有纳米胶束的水中将NaBH 4 添加到Pd(OAc) 2导致H 2和Pd纳米颗粒的产生。随后二取代炔烃的还原以高产率提供Z-烯烃。这些反应是一般的,在环境温度下在水中发生,并且提供水性反应混合物的循环以及低的总 E 因子。
Electrophilic Iron Catalyst Paired with a Lithium Cation Enables Selective Functionalization of Non‐Activated Aliphatic C−H Bonds via Metallocarbene Intermediates
Combining an electrophilic iron complex [Fe(F pda)(THF)]2 (3) [F pda=N,N'-bis(pentafluorophenyl)-o-phenylenediamide] with the pre-activation of α-alkyl-substituted α-diazoesters reagents by LiAl(ORF )4 [ORF =(OC(CF3 )3 ] provides unprecedented access to selective iron-catalyzed intramolecular functionalization of strong alkyl C(sp3 )-H bonds. Reactions occur at 25 °C via α-alkyl-metallocarbene intermediates