Cyclopropylcarbinyl radical-mediated ring expansion to seven-membered carbocycles
作者:Eric J. Kantorowski、Babak Borhan、Saman Nazarian、Mark J. Kurth
DOI:10.1016/s0040-4039(98)00311-6
日期:1998.4
carbocycles can be prepared from the corresponding xanthate derivatives of bicyclo[4.1.0]heptan-1-methanol. In certain systems, an intermediate cycloheptyl radical appears to be kinetically favored over the cyclohexyl radical, but the direction of cyclopropylcarbinyl radical fragmentation is subject to substitution about the bicyclo[4.1.0]heptan-1-methyl ring.
Enecarboxylation with diethyl oxomalonate as an enophilic equivalent of carbon dioxide. A synthesis of allylcarboxylic acids
作者:Mary F. Salomon、Simon N. Pardo、Robert G. Salomon
DOI:10.1021/ja00325a014
日期:1984.6
On prepare une serie d'acides carboxyliques allyliques a partir des olefines correspondantes par un processus en deux etapes equivalent a: 1) une reaction ene avec l'oxomalonate de diethyle conduisant a l'ester α-hydroxymalonique; 2) une bisdecarboxylation oxydante de ce dernier
在制备 une serie d'acides carboxyliques allyliques a partir des ocoxyliques par un processus en deux etapes 等价物 a: 1) une 反应 ene avec l'oxomalonate de diethyle conduisant a l'ester α-hydroxymalonique; 2) une bisdecarboxylation oxydante de ce dernier
Oxone-mediated Methoxy Thiocyanation of 1,1-Disubstituted Olefins in Methanol
Reactions of 1,1-disubstituted olefins with oxone and ammonium thiocyanate in methanol gave the corresponding 1-methoxy-2-thiocyano adducts in various yields.
unexplored area for C−C bond formation. Herein 64 examples of β‐alkylated styrene derivatives, synthesized through the reactions of readily accessible feedstock olefins with β‐nitrostyrenes by ozone/FeII‐mediated radical substitutions, are reported. These reactions proceed with good efficiencies and high stereoselectivities under mild reaction conditions and tolerate an array of functional groups. Also demonstrated
烯烃C(sp 3)-C(sp 2)键的脱烯基烯基化作用一直是C-C键形成的未知区域。本文报道了64个β-烷基化苯乙烯衍生物的例子,这些例子是通过容易获得的原料烯烃与β-硝基苯乙烯通过臭氧/ Fe II介导的自由基取代反应而合成的。在温和的反应条件下,这些反应具有良好的效率和较高的立体选择性,并且可以耐受一系列官能团。还证明了该策略通过产品的几种合成转化以及天然产物异吗啡丁和药物(E)-美丹尼丁的合成的适用性。
Synthetic Photochemistry. LX. One-pot Formation of Spirocyclic 3-Acetyl-2-hydroxy-2-cyclopentenone Derivatives from Methylenecycloalkanes and Methyl 2,4-Dioxopentanoate
of proto-photocycloadducts of methyl 2,4-dioxopentanoate to methylenecycloalkanes and -alkenes spontaneously caused retro-benzilic acid rearrangement in high yields. The results are utterly different from those of sterically-crowded acyclic alkenes, with which the rearrangement occurred by thermolysis as a minor process.