Norbornadiene-functionalized triazatriangulenium and trioxatriangulenium platforms

• Roland Löw,
• Talina Rusch,
• Tobias Moje,
• Fynn Röhricht,
• Olaf M. Magnussen and
• Rainer Herges

Beilstein J. Org. Chem. 2019, 15, 1815–1821, doi:10.3762/bjoc.15.175

• ; quadricyclane; self-assembled monolayers; TATA platform; thermal isomerization; TOTA platform; Introduction Recently, we discovered that the thermochemically forbidden cis–trans isomerization of azobenzenes can be efficiently catalysed by a very peculiar mechanism on bulk gold [1]. In heterogeneous catalysis

• the mechanisms of bulk metal catalysis and open new ways to design new catalytic systems. Towards this end, and following the “platform concept”, we designed a cyano-substituted norbornadiene, which is functionalized with an acetylene spacer on a TATA platform to investigate an eventual “spin

• -cyanonorbornadiene (4) was subjected to halogen–metal exchange with n-BuLi and coupled with the central atom of the TOTA platform 8 to obtain the norbornadiene-functionalized TOTA platform 3 (22%, Scheme 1). The synthesis of the corresponding TATA platform including an additional 2-methylphenyl group (2) was

Diazocine-functionalized TATA platforms

• Roland Löw,
• Talina Rusch,
• Fynn Röhricht,
• Olaf Magnussen and
• Rainer Herges

Beilstein J. Org. Chem. 2019, 15, 1485–1490, doi:10.3762/bjoc.15.150

• ordered monolayers on Au(111) surfaces. Keywords: cis–trans isomerization; diazocine; molecular switch; photochrome; self-assembled monolayers; TATA platform; Introduction Catalysts increase chemical reaction rates by lowering the activation energies and thus create more favorable reaction pathways [1

• reaction barriers (trans-twist→cis-boat) for both compounds of approximately 23 kcal mol−1 (96 kJ mol−1). Obviously, the TATA platform and the ethynyl spacer have only marginal effects on the isomerization process. Hence, the diazocines 1 and 2 are ideal candidates to investigate the effect of bulk gold as

• of the formed hydrazine (16%). The unprotected ethynyldiazocine 8 was deprotonated with potassium hydroxide and connected to the central carbon atom of the TATA platform 9 (synthesized according to Laursen and Krebs [28]) to obtain target para-diazocine mounted on the octyl-substituted TATA platform