action: A multifunctional rhodium catalyst system enables the simultaneous catalysis of two distinct transformations, hydroformylation of an alkene and reduction of an aldehyde, in a highly selective manner. This one‐pot/two‐step process is controlled by the cooperative action of two different supramolecular ligandsystems and transforms terminal alkenes into C1‐chain‐elongated linear alcohols.
Reaction of Acetals with Various Carbon Nucleophiles under Non-Acidic Conditions: CC Bond Formation via a Pyridinium-Type Salt
作者:Hiromichi Fujioka、Kenzo Yahata、Tomohito Hamada、Ozora Kubo、Takashi Okitsu、Yoshinari Sawama、Takuya Ohnaka、Tomohiro Maegawa、Yasuyuki Kita
DOI:10.1002/asia.201100812
日期:2012.2.6
substitution reactions of acetals with carbon nucleophilesvia the pyridinium‐type salts generated by the treatment of acetals with TESOTf‐2,4,6‐collidine or 2,2′‐bipyridyl have been developed. Various carbon nucleophiles, such as organocuprates, silyl enol ethers, enamines, etc., reacted with the pyridinium‐type salts to give the corresponding substituted products in good yields. The reactions proceeded
Organic Chemistry Using Weakly Electrophilic Salts: Efficient Formation of <i>O</i>,<i>O</i>-Mixed, <i>O</i>,<i>S</i>- and <i>N</i>,<i>O</i>-Acetals
作者:Hiromichi Fujioka、Takashi Okitsu、Takuya Ohnaka、Ruichuan Li、Ozora Kubo、Kazuhisa Okamoto、Yoshinari Sawama、Yasuyuki Kita
DOI:10.1021/jo071187g
日期:2007.10.1
A mild and efficient method for the preparation of O,O-mixed, O,S- and N,O-acetals from symmetrical O,O-acetals has been developed. Thus, the treatment of symmetrical O,O-acetals with TESOTf and 2,4,6-collidine formed weakly electrophilic collidinium salts. The addition of nucleophiles, such as an alcohol, lithium thioxide, and sodium azide, to the salts afforded the corresponding O,O-mixed, O,S- and N,O-acetals in good yields. The reaction proceeded under weakly basic conditions. No overreaction then occurred and many acid-labile functional groups could remain intact.