A new method for the synthesis of diamantane by hydroisomerization of binor-S on treatment with sulfuric acid

Abstract

A new method was developed for the direct synthesis of the second representative of the homologous series of diamond-like hydrocarbons, diamantane, in 65% yield by hydroisomerization of the norbornadiene dimer, endo-endo-heptacyclo[8.4.0.02,12.03,8.04,6.05,9.011,13]tetradecane (binor-S) on treatment with concentrated sulfuric acid (98%). In the presence of H2SO4 of lower concentration (75–80%), the reaction stops after the hydrogenation step giving endo-endo-pentacyclo[7.3.1.12,5.18,10.03,7]tetradecane in 68% yield with excellent selectivity (100%).

Synthesis of Polycyclic Hydrocarbons C14H20by Hydrogenation ofexo–exo-,exo–endo-,endo–exo-, andendo–endo-Hexacyclo[9.2.1.02,10.03,8.04,6.05,9]tetradec-12-enes with H2SO4and Isomerization of the Products to Diamantane Induced by Ionic Liquids

“…In a previous study, 40 we accomplished the direct synthesis of diamantane 1 using H 2 SO 4 (98%) from the heptacyclic norbornadiene dimer, binor-S, which has four H atoms less in the molecule than diamantane. This fact indicates that H 2 SO 4 promotes hydrogenation and isomerization of binor-S.…”

Synthesis of polycyclic hydrocarbons C14H20 by hydrogenation of exo-exo-, exo-endo-, endo-exo-, and endo-endo- hexacyclo[9.2.1.02,10.03,8.04,6.05,9]tetradec-12-enes with H2SO4 and isomerization of the products to diamantane induced by ionic liquids

“…In a previous study [31], we accomplished direct synthesis of diamantane (1) using H2SO4 (98%) from the heptacyclic norbornadiene dimer, binor-S, which has four H atoms less in the molecule than diamantane. This fact indicates that H2SO4 promotes hydrogenation and isomerization of binor-S.…”

Hexacyclotetradecenes as Polycyclic Fused exo-Norbornene Monomers: Synthesis of Cyclic Olefin Copolymers via Ti-Catalyzed Efficient Polymerization

“…38 A two-cyclopropane-containing dimer, heptacyclo[8.4.0.0 2,12 .0 3,8 .0 4,6 .0 5,9 .0 11,13 ]tetradecane, known as Binor-S, has been known for decades; however, its reactivity still remains largely unexplored. [40][41][42][43][44][45][46][47][48][49] In a previous study, the hydroisomerization of Binor-S using sulfuric acid produced diamantane, whereas an ionic liquid, [Et3NH][HSO4], facilitated the formation of hexacyclo[8.4.0.0 2,7 .0 3,14 .0 4,8 .0 9,13 ]tetradec-5-ene (1a) and hexacyclo[6.6.0.0. 2,6 .0 5,14 .0 7,12 .0 9,13 ]tetradec-3-ene (1b).…”

“…2,6 .0 5,14 .0 7,12 .0 9,13 ]tetradec-3-ene (1b). 48 Based on this, herein, we focused on 1a and 1b as NB-based monomers featuring exo-fused polycyclic rings and a bridgehead tertiary carbon connected to the other cyclic moiety. This study represents the first attempt to investigate the polymerizations of 1a and 1b.…”