56630-33-2Relevant articles and documents
Tandem Regioselective Hydroformylation-Hydrogenation of Internal Alkynes Using a Supramolecular Catalyst
Fang, Weiwei,Breit, Bernhard
supporting information, p. 14817 - 14821 (2018/10/24)
New supramolecular ligands containing an acyl guanidine function were designed based on the strategy of increasing the π-acceptor ability of phosphine ligands by introducing electron-withdrawing groups. By applying this novel catalytic system, a general protocol for the Rh-catalysed hydroformylation-hydrogenation of unsymmetrical internal alkynes, functionalized with a carboxylic acid, was found to furnish aliphatic aldehydes in high regio- and chemoselectivities. Control experiments confirm the enzyme-like supramolecular catalyst mode of action.
A new synthesis of β,γ-alkenyl carboxylic acids from α,β-alkenyl carboxylic acid chlorides and α,β-alkenyl aldehydes with one-carbon elongation
Satoh, Tsuyoshi,Nakamura, Akira,Iriuchijima, Atsuko,Hayashi, Yasumasa,Kubota, Ko-Ichi
, p. 9689 - 9696 (2007/10/03)
Reaction of the lithium α-sulfinyl carbanion of chloromethyl phenyl sulfoxide with α,β-alkenyl carboxylic acid chlorides gave γ,δ-alkenyl α-chloro-β-keto sulfoxides in variable yields. The keto sulfoxides were also synthesized from α,β-alkenyl aldehydes in two steps in good overall yields: addition of the lithium α-sulfinyl carbanion of chloromethyl phenyl sulfoxide to α,β-alkenyl aldehydes followed by oxidation of the adducts with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone or Dess-Martin periodinane. These products were treated in sequence with potassium hydride, tert-butyllithium, and 5% aqueous sodium hydroxide, in one flask to give β,γ-alkenyl carboxylic acids with one-carbon elongation in good yields. The procedure offers a new method for synthesizing β,γ-alkenyl carboxylic acids from α,β-alkenyl carboxylic acid chlorides and α,β-alkenyl aldehydes with one-carbon elongation.
A Stereospecific Access to Allylic Systems Using Rhodium(II)-Vinyl Carbenoid Insertion into Si-H, O-H, and N-H Bonds
Bulugahapitiya, Priyadarshanie,Landais, Yannick,Parra-Rapado, Liliana,Planchenault, Denis,Weber, Valery
, p. 1630 - 1641 (2007/10/03)
Rhodium-catalyzed decomposition of α-vinyldiazoesters in the presence of silanes, alcohols, ethers, amines, and thiols have been shown to produce the corresponding α-silyl, α-hydroxy, α-alkoxy, α-amino, and α-thioalkoxy esters in generally good yield with a complete retention of the stereochemistry of the double bond of the diazo precursor. An extension of the process in homochiral series has also been devised using either a chiral auxiliary attached to the ester function or achiral α-vinyldiazoesters and Doyle's chiral catalyst Rh2(MEPY)4. In the former approach, pantolactone as chiral auxiliary gave diastereoselectivities of up to 70%, while the second approach produced the desired allylsilane with ee as high as 72%. On the other hand, Rh2(MEPY)4-catalyzed insertion into the O-H bond of water led to poor or no enantioselectivity in good agreement with recent literature reports.
