Monosubstituted 3,3‐Difluorocyclopropenes as Bench‐Stable Reagents: Scope and Limitations
作者:Pavel S. Nosik、Mykola O. Pashko、Andrii S. Poturai、Denys A. Kvasha、Alexander E. Pashenko、Alexander B. Rozhenko、Sergiy Suikov、Dmitriy M. Volochnyuk、Sergey V. Ryabukhin、Yurii L. Yagupolskii
DOI:10.1002/ejoc.202100921
日期:2021.12.21
A protocol for the synthesis of gem-difluorocyclopropenes was developed, based on Ruppert-Prakash reagent slow addition. The empiric observations allow to predict whether the compound could be stocked neat, as a solution, or only used after generation in situ.
General synthesis of cyclopropenones and their acetals
作者:Masahiko Isaka、Satoshi Ejiri、Eiichi Nakamura
DOI:10.1016/s0040-4020(01)88873-6
日期:——
Metalated cyclopropenone acetals 5 react with a variety of electrophiles, including alkyl halides, carbonylcompounds, vinyl iodides, vinyl triflates, and aryl iodides, to give substituted cyclopropenone acetals in high yield. Hydrolysis of the acetal under acidic conditions gives the corresponding cyclopropenone. The reaction sequence has realized an efficient synthesis of an antibiotic penitricin
aldehydes via the iodoformylation of terminalalkynes with TMSCF3 and NaI. This synthetic method uses inexpensive and easy-to-handle chemical feedstocks and employs a commercially available CuI catalyst. It can transform a broad range of terminalalkynes into bis-electrophile (E)-β-iodo-α,β-unsaturated aldehydes with excellent chemoselectivity, regioselectivity, and stereoselectivity. Moreover, it
在此,我们描述了一种通过末端炔烃与 TMSCF 3和 NaI的碘甲酰化合成 ( E )-β-碘-α,β-不饱和醛的方法。这种合成方法使用廉价且易于处理的化学原料,并采用市售的 CuI 催化剂。它可以将多种末端炔烃转化为具有优异化学选择性、区域选择性和立体选择性的双亲电子( E )-β-碘-α,β-不饱和醛。此外,证明该协议具有丰富的有机反应性。
Palladium-Catalyzed Ring-Opening Reaction of Cyclopropenones with Vinyl Epoxides
We report herein the Pd-catalyzed selective ring-opening reaction of cyclopropenones with vinyl epoxides. By using a commercially available Pd2(dba)3·CHCl3–BINAP catalyst, a wide range of conjugated alkadienyl carboxylates could be accessed in good yield and excellent regioselectivity. The new application of zwitterionic π-allyl palladium intermediates has been demonstrated in organic synthesis.