Recent Progress in the Chemistry of Allenes

Abstract

Allenes are important compounds in organic and synthetic organic chemistry and therefore a large number of studies on their synthesis and reactions have been reported so far. We report the most recent methods for the synthesis of allenes, including optically active forms and fluorinated and gem-difluorinated allenes, in this paper. Reactions such as nucleophilic addition of allenes were classified and discussed in details according to the nature of the nucleophile either oxygen, nitrogen, carbon or sulfur, whereas, inter-and intra-molecular cycloadditions reactions with a variety of unsaturated functionality were separately discussed. A collection of some useful reactions such as coupling reactions of allenes mediated by organometallic reagents, intramolecular cyclization of allenes with tethered amines, asymmetric dihydroxylation, and epoxidation of allenes are also included.

Formation of Cyclic Allenes and Cumulenes by Cooperative Addition of Frustrated Lewis Pairs to Conjugated Enynes and Diynes

“…Allenes and cumulenes are not only synthetically important substrates; [1] they are also structurally interesting organic compounds, especially when incorporated into small and medium-sized ring systems. In this context allene and cumulene units may introduce substantial strain if their carbon frameworks become markedly distorted from the usual geometries.…”

Bifunctionalized Allenes. Part XIII. A Convenient and Efficient Method for Regioselective Synthesis of Phosphorylated α-Hydroxyallenes with Protected and Unprotected Hydroxy Group

“…The synthetic potential of functionalized allenes has been thoroughly explored in recent years. The research in that area has led to the development of novel methods for the construction of a variety of functionalized heterocyclic and carbocyclic systems [9,10,11,12,13].…”

Regio- and stereoselective Diels-Alder reaction of diphenyl 5-methylhexa-1,3,4-trien-3-yl phosphine oxide with N-(4-substituted-phenyl)maleimides and maleic anhydride

“…31 During our previous works concerning electrophilic cyclization reactions of alkatrienyl phosphine oxides, we were able to show that 1-37 and 3-vinylallenyl 38 phosphine oxides are readily accessible by [2,3]-sigmatropic rearrangement of the corresponding 1-and 3-vinylpropargylic phosphinites, formed in the reactions of the corresponding -alkynols with diphenylphosphinous chloride.…”

“…An impressive number of carbo-and heterocyclic systems has been prepared from allenic starting materials. [1][2][3][4][5][6] Due to the fact that it allows the selective formation of two carbon-carbon bonds and up to four centers of chirality in a single step, the Diels-Alder reaction is perhaps one of the most important transformations in organic chemistry and is probably the most valuable and most applied reaction in synthetic organic chemistry. [7][8][9][10][11] Among the many different dienes and dienophiles employed in Diels-Alder reaction, allenes have played only a minor role.…”