Dibromopyrrole derivatives

V. cauliformis (Sharma and Burkholder, 1967), while the related compound 39 was isolated from V. lacunosa (Borders et al., 1974). From another sponge, Agelas oroides, the dibromopyrrole derivative 40 was isolated (Forenza et al., 1971), and from Disidea herbacea the pentabromophenol 41 was obtained (Sharma and Vig, 1972). Only two examples of chlorine-... 

Palladium-catalyzed Suzuki coupling was used to convert the now readily available 3,4-dibromopyrrole derivative into the core structures of different pyrrole alkaloids. 

Tour has utilized dibromopyrrole 108 to prepare zwitterionic diiodopyrrole 110, which in turn was employed in a synthesis of diphenyl derivative 111 and pyrrole polymers [10,11],... 

A spermidine derivative with two 4,5-dibromopyrrole-2-carbamyl units, pseudo-ceratidine (120), has been isolated from the sponge Pseudoceratina purpurea as an antifouling compound [145]. 

Dibromopyrrole 1084 (R = Br) and benzyne generated from anthranilic acid and isoamyl nitrile gave dibromo-derivative 1086, the metallation of which led to product 1087 (Scheme 211) <20050L1003>, which was later successfully used in a cyclotrimerization reaction. 

Bromo- and 2-chloropyrroles, unstable compounds, can be prepared by direct halogenation of pyrrole.Using l,3-dibromo-5,5-dimethylhydantoin as brominating agent, both 2-bromo- and 2,5-dibromopyrroles can be obtained, the products stabilised by immediate conversion to their A-/-butoxycarbonyl derivatives. Conversely, bromination of A-Boc-pyrrole with A-bromosuccinimide gives the 2,5-dibromo derivative. ... 

Boc-pyrrole has been coupled both through the 2-boronic acid derivative and the 2-trimethyl-stannyl derivative, both of which can be prepared from the lithiopyrrole <91S613>. Cross-coupling of l-Boc-2,5-dibromopyrrole with l-Boc-2-trimethylstannylpyrrole gave a tripyrrole (Scheme 129) <91SM403>. 

Pyrrole-Benzene. Copolymers of pyrrole and benzene have been synthesized from 2-phenylpyrrole and l,4-bis(2-pyrrol-yl)phenyl-ene [802] (Fig. 53a). Chemical syntheses of similar copolymers have been carried out by cyclization of a polyphenylene diketone in the presence of ammonia [803] (Fig. 54). Pd(0)-catalyzed coupling of boronic acid derivatives of 1,4-bisdodecylbenzene and 2,5-dibromopyrrole has also been used [804]. A series of l,4-bis(2-pyrrol-2yl)aiylenes have been synthesized and chemically and elec-trochemically polymerized as well [805] (Fig. 53b). 

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