Recent synthetic developments

In this section, the literature about Diels-Alder reactions will be presented in a conceptual and illustrative way. After a profound introduction dealing with the development of mechanistic understanding of the Diels-Alder reaction, some interesting recent synthetic developments and applications will be presented. The reaction types and fields of interest are structured in such a way that they can be easily linked to ongoing research from the past ten years. Special attention will be paid to the application of chiral auxiliaries and chiral Lewis acids in asymmetric Diels-Alder reactions. 

Paquette, Leo A. Recent synthetic developments in polyquinane chemistry. 

Paquette, L. A. Recent Synthetic Developments in Polyquinane Chemistry. 119, 1-158 (1984). 

As mentioned in the introduction, recent synthetic developments now allow access to the 1,2-thiazine structure via disconnection type C (Figure 23). This process can be accomplished by a Friedel-Crafts-type cyclization of sulfamoyl chlorides. The initial report of this reaction utilized a stoichometric amount of aluminium chloride promoter <19920PP463>. Recently, however, A -ethyl phenethylsulfamoyl chloride 214 was shown to undergo Friedel-Crafts cyclization to form sultam 215 with just a catalytic amount of In(OTf)3 (Equation 33) <2002SL1928>. 

Most of the recent synthetic developments in the field of radical cyclization have involved the reactions of carbon-centered radicals with alkenes and alkynes. Other useful acceptors include allenes,31 dienes30 and vinyl epoxides.32 The same methods are used for cyclizations to these acceptors as for radical additions, and the preceding chapter should be consulted for specific details on an individual method (the organization of this section parallels that of Section 4.1.6). Selection of a particular method to conduct a proposed cyclization is based on a variety of criteria, including the availability of the requisite pre-... 

An earlier review 4) from this laboratory has summarized the initial, collective phase of this development. As a sequel, we propose not only to review the recent synthetic developments but also to emphasize the many applications of diamonoid substrates for testing various theories of physical-organic chemistry... 

Ballini, R. and Petrini, M. 2004. Recent synthetic developments in the nitro to carbonyl conversion (Nef reaction). Tetrahedron, 60(5) 1017-47. 

Kouznetsov VV (2009) Recent synthetic developments in a powerful imino Diels-Alder reaction (Povarov reaction) application to the synthesis of V-polyheterocycles and related alkaloids. Tetrahedron 65 2721-2750... 

It is worth repeating that one of the real advantages of preparing interfaces by simple adsorption of a preformed polymer is ease of fabrication. Another is chemical versatility which is limited only by the synthesis of new polymers. One recent synthetic development is reductive loss of Cl" followed by re-oxidation and pyridyl incorporation, all of which can be made to occur within a preformed electrode-polymer interface, as shown on the next page. The work is described in another paper in this volume (34). Another development is the preparation of an extended series of related PVP polymers based on Ru-bpy chemistry, -(py)Ru(bpy)2X2+... 

A major basis for the advancement in macro-molecular functionality is our improving ability to control the macromolecular and supramolecular structures in great detail. Dense and cascade-type branching provided access to three-dimensional molecules, which do not interpenetrate but interact via their surfaces. Recent synthetic developments include microgels,15 17 dendrimers,18-26 and arborescent graft... 

Recent Synthetic Development in the Nitro to Carbonyl Conversion (Nef Reaction) Ballini, R. Petrini. M. Tetrahedron 2004, 60,1017. 

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