The Synthesis and Some Reactions of 1,2-Cyclononadiene and 1,2-Cyclodecadiene

Allenes

“…Br X = Br or Cl [23] ( Dehydrohalogenation of 9-10 carbon atom rings leads mainly to cyclic aliènes with some cycloalkyne by-product [28,29]. The cycloalkyne of only 9-10 carbon atom rings is more highly strained than that of the aliènes.…”

Palladium-Catalyzed SN2′-Cyclization of Ambivalent (Bromoalkadienyl)malonates: Preparation of Medium- to Large-Membered Endocyclic Allenes

“…Because of their propadiene structures, they show distinctive steric and electronic properties and have emerged as highly interesting target molecules in organic synthesis. , Incorporation of an allenic substructure into a carbocycle creates a peculiar topological property . Although various endocyclic allenes have been prepared and reported so far, most of their synthetic methods construct an allenic motif within a preformed carbocycle precursor. − Two of the most widely applicable methods in the synthesis of endocyclic allenes, namely the ring enlargement of cycloalkenes via the corresponding gem -dibromobicyclo­[ n .1.0]­alkenes by the Doering–Moore–Skattebøl reaction and dehydrohalogenation of 1-halocycloalkenes, are also classified in this category. Another approach to the endocyclic allenes is cyclization of preformed acyclic allenes .…”

Electrophilic Additions to Allenes. VIII. The Kinetics and Mechanism of the Addition of Benzenesulphenyl Chloride to Allenes

“…The addition of arenesulphenyl chlorides to allenes has been extensively studied by a number of workers [1][2][3][4][5][6][7][8][9][10][11][12][13][14] . As a result of these investigations, a mechanism has been proposed involving rate-determining formation of alkylidenethiiranium ions which are subsequently attacked by chloride ion in the product determining step (see Scheme 1).…”