Radical pathways of coal dissolution in hydrogen donor media. 2. .beta. Scission and 1,2 aryl migration reactions of radicals derived from methylindans and tetralin at 327-627.degree.C
通过氢化茚羧酸及其衍生物,研究了向α,β-不饱和羧酸加氢的立体化学。在存在和不存在辛可尼丁作为手性改性剂的情况下,在Pd / Al 2 O 3上进行实验。在所有情况下,氢化都是通过将两个氢原子向化学吸附的底物进行底侧顺式加成而发生的。反式的形成由于底物中的CC键异构化以及空间位置不利的不饱和分子的吸附和氢化,可观察到高达72%的异构体。N碱促进了“颠倒”位置的吸附。3-甲基茚-2-羧酸的氢化提供了高达45%的ee。由于Pd在CC键迁移中具有很高的活性,只有在异构化可忽略不计的情况下,才能获得良好的ee。
Catalyst systems consisting of supported or unsupported transition metal catalysts which have modifiers on the surface. The modifiers have sulphur-containing functionalities (G
0
). In addition, the modifiers may have a spacer (Sp) and a Bronsted-basic, Bronsted-acidic or Lewis-basic functionality (G
1
). The catalyst systems may be used for hydrogenation, reductive alkylation and reductive amination.
Disclosed is the vapor phase cyclodehydration of an aldehyde or ketone over a solid Lewis acid as catalyst to make indene or a substituted indene according to the equation: ##STR1##
Three-dimensional aliphatic fused and bridged rings are key pharmacophores in drugs and bioactive natural products. Here, we reported an organocatalytic visible-light induced dearomative cycloaddition of (hetero)arenes, with organic light-emitting diode material 4CzIPN or readily accessible thioxanthone as photocatalyst. A series of cyclobutane-fused polycyclic structures and bridgedbicyclo scaffolds were prepared