Dehydrierung cyclischer tertiärer Amine unter Reaktionsbeteiligung von enantiomeren nucleophilen Nachbargruppen / Dehydrogenation of Cyclic Tertiary Amines with Neighbouring of Enantiomeric Nucleophiles
Acid-Assisted Ru-Catalyzed Enantioselective Amination of 1,2-Diols through Borrowing Hydrogen
作者:Li-Cheng Yang、Ya-Nong Wang、Yao Zhang、Yu Zhao
DOI:10.1021/acscatal.6b02959
日期:2017.1.6
Here, we present a highly enantioselectivesynthesis of 1,2-amino alcoholsfrom readily available racemic 1,2-diols through a borrowinghydrogen process. An intriguing acid effect was discovered for this Ru-catalyzed amination reaction, which led to a significant improvement of the stereoselectivity of the process. Preliminary mechanistic studies suggest a scenario of Brønsted acid-assisted dynamic
Boranes in Synthesis. 6. A New Synthesis of .beta.-Amino Alcohols from Epoxides. Use of Lithium Amides and Aminoborane Catalysts To Synthesize .beta.-Amino Alcohols from Terminal and Internal Epoxides in High Yield
作者:Clifford E. Harris、Gary B. Fisher、David Beardsley、Lawrence Lee、Christian T. Goralski、Lawrence W. Nicholson、Bakthan Singaram
DOI:10.1021/jo00104a034
日期:1994.12
A study of the conversion of terminal and internal epoxides to the corresponding beta-amino alcohols using simple primary and secondary lithium amides has been carried out. Thus, styrene oxide and 1,2-epoxydodecane react directly with primary and secondary lithium amides in THF at 25 degrees C to give a single regioisomer of the corresponding beta-amino alcohols in 80-100% isolated yields. Since internal epoxides are known to yield predominantly allylic alcohols when reacted with lithium amides, we employed a series of aminoborane Lewis-acid catalysts, generated in situ, to suppress formation of the allylic alcohols. Thus, the reaction of cyclohexene oxide with a variety of primary and secondary lithium amides at 34 degrees C in diethyl ether in the presence of a catalytic amount of B-bromo-9-BBN afforded the corresponding beta-amino alcohols in 70-95% isolated yield.
Beardsley David A., Fisher Gary B., Goralski Christian T., Nicholson Lawr+, Tetrahedron Lett, 35 (1994) N 10, S 1511-1514
作者:Beardsley David A., Fisher Gary B., Goralski Christian T., Nicholson Lawr+