A short and versatile route to chiral spiroketal skeletons

Different chiral spiroketal skeletons are obtained, in a versatile manner, by iterative alkylations of acetone N,N-dimethylhydrazone with iodides 2 followed by a one-pot deprotection/spirocyclization sequence. This methodology has been applied successfully to the synthesis of 1,7-dioxaspiro[5.5]undecane and 1,6-dioxaspiro[4.5]decane systems.     

Palladium‐Catalyzed Intermolecular Aryliodination of Internal Alkynes

A completely atom economical palladium‐catalyzed addition reaction has been developed to stereoselectively access functionalized tetrasubstituted alkenyl iodides. The palladium catalyst, which bears an electron‐poor bidentate ligand rarely employed in catalysis, is essential to promote the high yielding and chemoselective intermolecular reaction between equimolar amounts of an alkyne and an aryl iodide. This new carbohalogenation reaction is an attractive alternative to traditional synthetic methods, which rely on multistep synthetic sequences and protecting‐group manipulations.     

铜催化苯甲酰亚胺高烯丙酯的分子内胺化全氟烷基化反应

报道了铜催化苯甲酰亚胺高烯丙酯底物的分子内胺化全氟烷基化反应. 该反应以全氟碘代烷为全氟烷基化试剂, 醋酸铜为催化剂, 邻菲啰啉为配体, 在醋酸银存在下以中等的收率实现苯甲酰亚胺高烯丙酯底物末端双键的胺化全氟烷基化, 最终生成1,3-噁嗪类分子. 多种官能团取代的苯甲酰亚胺高烯丙酯和具有不同碳链长度的全氟碘代烷烃都能适用于该反应, 为多氟烷基取代的1,3-噁嗪类化合物的合成提供了一种简洁的方法. 多氟烷基取代的1,3-噁嗪类化合物还可在温和条件下高效转化为γ氨基醇衍生物. 初步的机理研究证明该反应经历了全氟烷基自由基对碳碳双键的亲电加成, 之后苯甲酰亚胺基团作为分子内亲核性胺源经历分子内亲核取代途径生成1,3-噁嗪骨架.     

New electrophilic iodochlorinating systems based on iodine (+1)

Two new convenient systems for electrophilic iodochlorination of olefins are proposed: KIO₃+I₂+HCl (in aqueous solutions) and KlCl₄+I₂ (in organic solvents). Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 877–878, April, 1997.     

Reductive carbonylation of aryl and heteroaryl iodides using Pd(acac)2/dppm as an efficient catalyst

Palladium catalyzed simple and efficient protocol for reductive carbonylation of aryl and heteroaryl compounds has been developed. The formylation of aryl and heteroaryl iodides takes place in the presence of Pd(acac)₂/dppm catalyst at 10 bar pressure of synthetic gas to give the desired aromatic and heteroaromatic aldehydes in good to excellent yields. Easy work-up, stability of the catalyst, low catalyst loading and less reaction time are the advantages of this method.     

Copper‐Catalyzed Cross‐CouplingLigand‐Free Conditions Reaction of Thiols with Aryl Iodides under

Commercially available CuO powder is found to be a suitable catalyst for C‐S coupling reaction between aryl‐ and alkyl thiols and aryl iodides. Functional groups including halides, ketone, unprotected amine and heterocycles were tolerated by the reaction conditions employed.     

Copper bis(2,2,6,6-Tetramethyl-3,5-heptanedionate)–Catalyzed Coupling of Sodium Azide with Aryl Iodides/Boronic Acids to Aryl Azides or Aryl Amines

This work reports an efficient protocol for the coupling reaction of aryl iodides/boronic acids with sodium azide to aryl azides/amines in the presence of copper bis(2,2,6,6-tetramethyl-3,5-heptanedionate) Cu(TMHD)₂ catalyst. The Cu(TMHD)₂ catalyst is a structurally well-defined, O-containing, air- and moisture-stable, transition-metal complex and works at mild reaction conditions. It was observed that aryl azides can be reduced further to corresponding aniline derivatives using the same catalyst under basic reaction conditions for a prolonged period.

[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.]     

Efficient ligand-free nickel-catalyzed C-S cross-coupling of thiols with aryl iodides

NiCl₂·6H₂O efficiently catalyzes the C-S bond formation by the cross-coupling of aryl iodides with thiols in tetrabutylammonium bromide (TBAB) in excellent yield. The reaction functions in air and the NiLn-TBAB can be recovered and recycled without the loss of activity.     

CuI‐Mediated Trifluoromethylations with Stannanes. Preliminary Communication

(Trifluoromethyl)stannane reagents such as Bu₃SnCF₃ are effective in CuI‐mediated trifluoromethylation reactions of aryl iodides. The reactions proceed via the intermediacy of [CuCF₃] species.