钯催化烯烃的不对称马氏氢胺羰基化反应

一氧化碳参与的羰基化反应是有机合成中最重要的反应之一.烯烃的氢羰基化反应已经被广泛应用于药物、材料及精细化学品的工业生产中[1].例如,乙烯的甲氧羰基化反应被用于甲基丙烯酸甲酯的工业合成,然而,该领域仍有许多挑战性难题尚未得到有效解决.烯烃的氢胺羰基化反应能以原子经济性的方式合成酰胺,且已经实现该类反应的区域选择性控制...     

Reaction of Hydantoin with Boronic Acids

We have examined the reaction of hydantoin (=imidazolidine‐2,4‐dione) with (formylphenyl)boronic acids, where the addition of a boronic acid group is hoped to increase bioactivities. Addition of (2‐formylphenyl)boronic acid to hydantoin gave an unexpected azaborine compound, which presumably arises by initial formation of the (phenylmethylidene)hydantoin, with subsequent loss of H₂O to give the cyclized product. Reactions of (3‐formylphenyl)‐ and (4‐formylphenyl)boronic acids with hydantoin gave the corresponding [(Z)‐phenylmethylidene]hydantoins in good‐to‐excellent yields. Attempts to use (3‐formylthiophen‐2‐yl)boronic acid gave a product where the boronic acid group has been cleaved.     

The Efficient Palladium-Catalyzed Selective t Synthesis of Benzenesulfonic Acids

α-Chloroalkyl aryl ethers has been obtained in good yields from phenols and aryl α-chloroalkyl sulfides.     

Convenient Synthesis of 1,8-Diiodoanthracene and Its Coupling with Thianthrene Boronic Acids

1,8-Diiodoanthracene has been prepared from commercially available 1,8-dichloroanthraquinone; it was shown to couple twice under Pd(0)-catalysis, with thianthrene 1- and 2-boronic acids giving 1,8-bis(thianthrenyl)anthracenes.     

Efficient Suzuki-Type Cross-Coupling of Enantiomerically Pure Cyclopropylboronic Acids

Optically active cyclopropanes (e.g. 1 ) can be prepared by the use of tartaric acid derivatives as chiral auxiliaries in the palladium-catalyzed cross-coupling of optically active cyclopropylboronic acids with electrophiles. The absolute configuration of the chiral carbon atom is retained, and the reaction proceeds with good yields and enantiomeric excesses. R=H, p-Ph, o-CO₂CH₃, p-CO₂CH₃, p-NO₂, o-OCH₃, m-OCH₃.     

Palladium-Catalyzed Cross-Coupling of Gem-Bromofluoroalkenes with Alkylboronic Acids for the Synthesis of Alkylated Monofluoroalkenes

Monofluoroalkenes are versatile fluorinated synthons in organic synthesis, medicinal chemistry and materials science. In light of the importance of alkyl-substituted monofluoroalkenes efficient synthesis of these moieties still represents a synthetic challenge. Herein, we described a mild and efficient methodology to obtain monofluoroalkenes through a stereospecific palladium-catalyzed alkylation of gem-bromofluoroalkenes with primary and strained secondary alkylboronic acids under mild conditions. This novel strategy gives access to a wide range of functionalized tri- and tetrasubstituted monofluoroalkenes in high yield, with good functional group tolerance, independently from the gem-bromofluoroalkenes geometry.     

Synthesis of Aldehydes by Organocatalytic Formylation Reactions of Boronic Acids with Glyoxylic Acid

Reported herein is a conceptually novel organocatalytic strategy for the formylation of boronic acids. New reactivity is engineered into the α‐amino‐acid‐forming Petasis reaction occurring between aryl boronic acids, amines, and glyoxylic acids to prepare aldehydes. The operational simplicity of the process and its ability to generate structurally diverse and valued aryl, heteroaryl, and α,β‐unsaturated aldehydes containing a wide array of functional groups, demonstrates the practical utility of the new synthetic strategy.     

Coupling Reactions of Anhydro-Aldose Tosylhydrazones with Boronic Acids

A catalyst-free coupling reaction between O-peracetylated, O-perbenzoylated, O-permethylated, and O-permethoxymethylated 2,6-anhydro-aldose tosylhydrazones (C-(β-d-glycopyranosyl)formaldehyde tosylhydrazones) and aromatic boronic acids is reported. The base-promoted reaction is operationally simple and exhibits a broad substrate scope. The main products in most of the transformations were open-chain 1-C-aryl-hept-1-enitol type compounds while the expected β-d-glycopyranosylmethyl arenes (benzyl C-glycosides) were formed in subordinate yields only. A mechanistic rationale is provided to explain how a complex substrate may change the well-established course of the reaction.     

Reaction of Sulfinic Acids with Heteroconjugated Alkenes

Abstract

The nucleophilic addition reactions of arenesulfinic acids with heteroconjugated alkenes have been studied. The structures of the sulfones thus obtained were confirmed by microanalytical and spectral methods. Kinetic parameters of the nucleophilic addition reactions were determined. Interactions are second-order reactions, but they are first order regarding each reagent. The influence of various substituents at the carbon–carbon double bond on the nucleophilic activity was studied.     

Palladium-Catalyzed Oxidative Carboacetoxylation of Activated Alkynes with Amino Acids

A palladium-catalyzed intramolecular oxidative carboacetoxylation reaction of alkynes with various amino acids has been demonstrated for the first time, forming pharmaceutically important 3-methyleneindolin-2-one. In the presence of Pd(OAc)₂ and ArI(OAc)₂, N-arylpropiolamides underwent tandem acetoxypalladation/C-H functionalization reactions with various Boc-amino acids to form corresponding methyleneindolin-2-ones bearing amino acid motifs in moderate to excellent yields.

[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.]     

镍催化的芳基硼酸偕二氟炔丙基化反应

偕二氟炔丙基取代的芳烃是一类非常重要的化合物, 但传统合成该类化合物的方法却存在很大局限性. 以过渡金属催化直接向芳烃偕二氟炔丙基化是一种高效简洁制备上述化合物的方法. 以廉价易得的Ni(NO₃)₂·6H₂O为催化剂, 首次实现了镍催化下芳基硼酸与α,α-二氟炔丙基溴的偶联反应. 该反应不仅温和高效、原料廉价易得、官能团兼容性良好, 而且还能进行克量级放大和对生物活性分子的后期氟修饰, 从而为新药研发提供了一种有效手段.     

Palladium-Catalyzed Arylfluorination of Alkenes: A Powerful New Approach to Organofluorine Compounds

Fluorine incorporation into organic molecules is often beneficial to their absorption, distribution, metabolism, and excretion (ADME) properties or bioactivity. As a consequence, organofluorine compounds have become quite common amongst drugs and agrochemicals, and their preparation is a highly important topic in both synthetic organic chemistry and pharmaceutical chemistry. One of the newly developed methods for accessing organofluorine compounds is Pd-catalyzed arylfluorination of alkenes. It is an olefin difunctionalization process that simultaneously introduces an aryl group and a fluorine atom into an alkene framework. This review provides a concise overview of this powerful and versatile method.