Rhodium-Catalysed Coupling of Allylic, Homoallylic, and Bishomoallylic Alcohols with Aldehydes and<i>N</i>-Tosylimines: Insights into the Mechanism
作者:Nanna Ahlsten、Belén Martín-Matute
DOI:10.1002/adsc.200900448
日期:2009.11
alkenols followed by reaction with aldehydes or N-tosylimines catalysed by rhodiumcomplexes has been studied. The catalytically active rhodiumcomplex is formed in situ from commercially available (cyclooctadiene)rhodium(I) chloride dimer [Rh(COD)Cl]2. The tandem process affords aldol and Mannich-type products in excellent yields. The key to the success of the coupling reaction is the activation of
已经研究了烯醇的异构化,然后与铑络合物催化的醛或N-甲苯胺反应。催化活性的铑配合物是由可商购的(环辛二烯)氯化铑(I)二聚体[Rh(COD)Cl] 2原位形成的。串联过程以优异的产率提供了羟醛和曼尼希型产品。于偶联反应的成功的关键是,催化剂的活化通过与postassium叔丁醇(叔丁醇钾),这促进了催化循环通过醇盐,而不是铑的氢化物。该机制使不需要的副产物的形成最小化。该机制已被1研究1 H NMR光谱和氘标记实验。
Regio- and Stereoselective Cross-aldol Reactions<i>via</i>Dialkylboryl Triflates
作者:Tan Inoue、Teruaki Mukaiyama
DOI:10.1246/bcsj.53.174
日期:1980.1
New borylating reagents, (Bu2BOTf and 9-BBNOTf), were prepared in high yields. The triflates reacted with enolizable ketones in the presence of tertiary amines to generate selectively one of the regioisomers of vinyloxyboranes by the choice of the reagents (the dialkylboryl triflates and tertiary amines) under mild reaction conditions. Vinyloxyboranes thus generated showed remarkable reactivity toward aldehydes to give only one regioisomer of the corresponding cross-aldols in good yields. High stereoselectivity was also observed in these reactions.
NEW DIRECTED CROSS-ALDOL REACTION USING 9-TRIFLUOROMETHYLSULFONYL-9-BORABICYCLO[3.3.1]NONANE
作者:Tan Inoue、Tadafumi Uchimaru、Teruaki Mukaiyama
DOI:10.1246/cl.1977.153
日期:1977.2.5
A directedcross-aldolreaction between two different carbonyl compounds by using 9-trifluoromethylsulfonyl-9-borabicyclo[3.3.1]nonane and tertiary amine is described. The reaction of methyl ketones with the other carbonyl compounds takes place in regiospecific manner to afford the corresponding cross-aldols in good yields through intermediates, 9-(1-methyl-1-alkenyl)oxy-9-borabicyclo[3.3.1]nonanes
Aldol reactions with a .alpha.-trimethylsilyl ketones. Dual roles of the trimethylsilyl group for regiospecific generation of enolate equivalents
作者:Tan Inoue、Toshio Sato、Isao Kuwajima
DOI:10.1021/jo00198a017
日期:1984.11
Dual roles of trimethylsilyl group for specific generation of enolates from β-ketoalkyltrimethylsilanes. Regiospecific preparation of two types of acyclic aldols