Lewis Acids: From Conventional Homogeneous to Green Homogeneous and Heterogeneous Catalysis

1 Review 1.1 Overview 1.2 Solid-phase organic synthesis (SPOS) 1.3 Beyond conventional solid-phase organic synthesis 1.4 The review 1.5 Some definitions 1.6 Solid-supported reagents and scavengers 1.7 Multi-step use of solid-supported reagents and scavenging reagents 1.8 Conclusions and future perspective 2 Introduction to the tables 2.1 Organisation of tables (reagent and catalyst section) 2.2 Representative data entry (reagent and catalyst section) 2.3 Organisation of tables (scavenging agents section) 2.4 Representative data entry (scavenging agents section) 3 Tables of reagents and catalysts 4 Tables of scavengers 5 Other relevant reviews 5.1 Insoluble polymers 5.1.1 Structure and physical properties (insoluble polymers) 5.1.2 General (insoluble polymers) 5.1.3 Reactions (insoluble polymers) 5.1.4 Miscellaneous (insoluble polymers) 5.2 Soluble polymers 5.2.1 General (soluble polymers) 5.2.2 Reactions (soluble polymers) 5.3 Inorganic solids 5.3.1 Structure and physical properties (inorganic solids) 5.3.2 General (inorganic solids) 5.3.3 Reactions (inorganic solids) 5.3.4 Miscellaneous (inorganic solids) 5.4 Miscellaneous supports 5.4.1 Structure and physical properties (miscellaneous supports) 5.4.2 General (miscellaneous supports) 5.4.3 Reactions (miscellaneous supports) 5.4.4 Miscellaneous (miscellaneous supports) 5.5 Purification strategies 5.5.1 Various supports (purification strategies) 5.5.2 Insoluble polymers (purification strategies) 6 Acknowledgements 7 Abbreviations 8 References 1 Review

Multi-step organic synthesis using solid-supported reagents and scavengers: a new paradigm in chemical library generation

This review is intended to give a wide scope on the uses of ion-exchange resins as catalysts or catalyst precursors in organic synthesis, for the preparation of fine or intermediate chemicals. Twelve families of reaction have been covered and presented according to the molecules to be synthesized, regardless of the anionic or cationic nature of the resins; thus, ∼300 references have been selected from January 1980. In acid-catalyzed reactions, the contribution of both Lewis acidity and Bronsted acidity are mentioned, and, when available, some aspects related to the stability or the recycling of the catalysts are reported. In base-catalyzed reactions, the importance of the thermal stability of anionic resins has been underlined. A table that is included as an appendix provides some data on the resins quoted here.

Organic Synthesis by Catalysis with Ion-Exchange Resins

This paper deals with the structure and chemistry of Nafion-H, the acidic form of Nafion, which is the trade name for a perfluorinated polymer manufactured by E. I. du Pont de Nemours & Co., Inc. Nafion-H and its salts are available from Dupont in both membrane and powder forms. Nafion composites with Teflon mesh (polytetrafluoroethylene) added to give increased mechanical strength are also available. In addition, sulfonated fluorocarbons modified with other chemically active polymers have been made by Dupont and by competing companies such as Ashai Chemical Industry Co., Ashai Glass Co., Tokuyama Soda Co., and Toya Soda Co.

Structure and chemistry of nafion-h: a fluorinated sulfonic acid polymer

We report the synthesis of BODIPYs with unsubstituted 1,7,8-positions and their dimerization by oxidative coupling with phenyliodine(III)-bis(trifluoroacetate) (PIFA). This dimerization was achieved for BODIPYs substituted in the 3,5-positions with either methyl or thienyl groups. The position and the type of the linkage in the resulting dimers depended on the nature of the substituent. The 3,5-dimethyl-BODIPY dyes were linked either via direct 1,1′-pyrrole–pyrrole coupling or via a 1,3′-methylene bridge. The 3,5-dithienyl-BODIPY dyes provided, in excellent yields, unique compounds linked exclusively via the α-thienyl positions. All dyes were unreactive in the 8-position. Electrochemical and spectroscopic measurements on the monomers and dimers provided evidence of interactions between the two halves of the dimers. Thus, oxidation and reduction potentials were split by up to 210 mV, and modest excitonic coupling and an internal charge transfer were observed in some cases.

Oxidative Coupling of 1,7,8-Unsubstituted BODIPYs: Synthesis and Electrochemical and Spectroscopic Properties

The reaction of thiophene with acyclic acid anhydrides in the presence of Nafion-H (fluorocarbon resin sulfonic acid) afforded the corresponding 2-acylthiophenes in moderate yields. Acylation with ...

The Nafion-H-catalyzed Acylation of Thiophene with Acid Anhydrides

皮膚刺激の少ない香粧品材料のための紫外線防御剤を開発することを目的として,シリカゲル表面に紫外線吸収能を有するシンナムアミド基を化学結合により固定化した表面修飾シリカゲルを作製した。可視および紫外光の透過率により評価を行ったところ,内部に細孔を持たない微粒子タイプのシリカゲルを素地として調製した化学修飾シリカゲルは,可視光に対して透明で,紫外線の透過を遮断する効果があることが認められた。また,これらの表面修飾シリカゲルを皮膚に塗布したところ,透明性が高く違和感がない特徴があった。

Kazuhiro Suetsugu

Papers

The Nafion-H-catalyzed Acylation of Thiophene with Acid Anhydrides

Preparation of Silica Gels Carrying Cinnamamido Groups and Their Protectional Function from Ultraviolet Rays

The nafion-h-catalyzed acylation of thiophene with acid anhydrides