Reaction of the lithium α-sulfinylcarbanion of chloromethyl phenyl sulfoxide with α,β-alkenyl carboxylic acid chlorides gave γ,δ-alkenyl α-chloro-β-keto sulfoxides in variable yields. The keto sulfoxides were also synthesized from α,β-alkenyl aldehydes in two steps in good overall yields: addition of the lithium α-sulfinylcarbanion of chloromethyl phenyl sulfoxide to α,β-alkenyl aldehydes followed
Synthetic Routes to Allenic Acids and Esters and Their Stereospecific Conversion to Butenolides
作者:James A. Marshall、Mark A. Wolf、Eli M. Wallace
DOI:10.1021/jo9618740
日期:1997.1.1
19 and 23 with inversion of configuration through treatment with Pd(Ph(3)P)(4), CO, and the appropriate alcohol in THF. These reactions proceeded with ca. 10% or less of racemization. The allenic esters 23 yielded the iodobutenolides 24 by reaction with IBr. Hydrogenolysis to the butenolide 25 was achieved with Pd(PPh(3))(4) and Bu(3)SnH. Alternatively, the allenic acids 27 could be prepared directly
Zinc-mediated carboxylations of allylic and propargylic halides in flow: synthesis of β-lactones <i>via</i> subsequent bromolactonization
作者:Patrick J. Sutter、Guowei Kang、Sreekumar Vellalath、Daniel Romo
DOI:10.1039/d2ra07715a
日期:——
Zinc-mediated carboxylation of allylic halides under flow conditions delivered β,γ-unsaturatedcarboxylicacids and subsequent bromolactonization provides a streamlined process for the synthesis of γ-bromo-β-lactones. The described process further demonstrates the utility of organozinc reagents prepared by passage of allylic halides through a metallic zinc column integrated into a flow process. Use
在流动条件下,锌介导的烯丙基卤化物的羧化作用会产生 β,γ-不饱和羧酸,随后的溴内酯化反应为 γ-溴-β-内酯的合成提供了一个简化的过程。所描述的过程进一步证明了通过将烯丙基卤化物通过集成到流动过程中的金属锌柱制备的有机锌试剂的效用。与间歇工艺相比,使用管中管反应器进行高效 CO 2引入可提高转化率并提高 β-内酯的总收率。所描述的流程也适用于炔丙基溴化物,用于合成丙二酸和炔丙酸。
Allenyllithium Reagents; V<sup>1</sup>. An Efficient Route to Functionalised Allenes
作者:Jean-Claude Clinet、Gérard Linstrumelle
DOI:10.1055/s-1981-29626
日期:——
CLINET, J. -C.;LINSTRUMELLE, G., SYNTHESIS, BRD, 1981, N 11, 875-878