78239-34-6

Upstream product

• 78239-40-4 1a,9a-dichloro-1,1-difluoro-1a,2,3,8,9,9a-hexahydro-1H-cyclopropanthracene 
• 50423-49-9 1,2-bis(iodomethyl)benzene 
• 39638-07-8 2,3-naphthoquinodimethane 
• 83142-99-8 1a,9a-dichloro-1,1-difluoro-1a,2,9,9a-tetrahydro-1H-cyclopropanthracene 
• 50423-48-8 1,2-di(prop-2-yn-1-yl)benzene 

Relevant academic research and scientific papers

254. Synthesis of Cyclopropanthracenes via Trapping of o-Naphthoquinodimethane

Cyclopropanthracenes 1, 1a, 1b are prepared in a 3-step synthesis starting from o-di(iodomethyl)benzene.The key step consists of trapping of o-naphthoquinodimethane (9) with 1,2-di- and tetrahalogenocyclopropenes (3, 3a, 4b).

Synthesis and Properties of 1,1-Dihalogenocyclopropanthracenes

The synthesis of 1,1-difluoro-1H-cyclopropanthracene (3) is described.The key step of the synthesis is the cycloaddition of 1,2-dichloro-3,3-difluorocyclopropene (6) to 2,3-dimethylidene-1,2,3,4-tetrahydronaphthalene (5).The 13C-NMR. spectrum of 3 is assigned on the grounds of C,F-coupling constants, selective H-decoupling and the resulting residual C,H-coupling.The 1,1-dichloro derivative 4 was synthesized by the same route, but could not be isolated pure.Experiments for the reduction to 1H-cyclopropanthracene (2) and for the ionization of 3 or 4 to the cation 16 failed.