33675-49-9Relevant academic research and scientific papers
Regioselective Synthesis of Polyheterohalogenated Naphthalenes via the Benzannulation of Haloalkynes
Lehnherr, Dan,Alzola, Joaquin M.,Lobkovsky, Emil B.,Dichtel, William R.
, p. 18122 - 18127 (2015)
Independent control of halide substitution at six of the seven naphthalene positions of 2-arylnaphthalenes is achieved through the regioselective benzannulation of chloro-, bromo-, and iodoalkynes. The modularity of this approach is demonstrated through the preparation of 44 polyheterohalogenated naphthalene products, most of which are difficult to access through known naphthalene syntheses. The outstanding regioselectivity of the reaction is both predictable and proven unambiguously by single-crystal X-ray diffraction for many examples. This synthetic method enables the rapid preparation of complex aromatic systems poised for further derivatization using established cross-coupling methods. The power and versatility of this approach makes substituted naphthalenes highly attractive building blocks for new organic materials and diversity-oriented synthesis.
Reactions with Phosphinealkylenes, XXXIX. - New Methods for the Preparation of 1-Bromoacetylenes and Enynes
Bestmann, Hans Juergen,Frey, Herbert
, p. 2061 - 2071 (2007/10/02)
1,1-Dibromoolefins 4 are obtained in good yield from the reaction of aldehydes 1 with triphenylphosphane (2) and carbon tetrabromide (3).Reaction of 4 with three moles of methylene(triphenyl)phosphorane (8) leads to the propargylidene(triphenyl)phosphoranes 11 which react with aldehydes to give the enynes 13.The ylides 11 can also prepared via the reaction of bromoacetylenes 7, which can be obtained from 4, with two moles of 8.This reaction sequence allows the synthesis of new retinoids with enyne structures from retinal.
