Molecular lambda shape light-driven dual switches: Spectroscopic and computational studies of the photoisomerization of bisazo Tröger base analogs

Synthesis of new cyano‐substituted analogues of Tröger's bases from bromo‐derivatives. A stereochemical dependence of long‐range (nJHH, n = 4, 5, and 6) proton–proton and proton–carbon (nJCH, n = 1, 2, 3, 4, and 5) coupling constants of these compounds

“…Although most published NMR data include complete assignment of 1 H, 13 C, and 15 N NMR chemicals shifts, the determination of long‐range 1 H‐ 1 H and 13 C‐ 1 H couplings has received little attention for the Tröger's bases . Recently, an interesting NMR study has been reported for the EE, EZ, and ZZ photoisomerization of disazo Tröger's base analogs . In general, review of the literature pertaining to multiplicity patterns of various types of Tröger's bases shows that the multiplicity of protons was generally oversimplified.…”

“…[30][31][32][33][34][35] Recently, an interesting NMR study has been reported for the EE, EZ, and ZZ photoisomerization of disazo Tröger's base analogs. [36] In general, review of the literature pertaining to multiplicity patterns of various types of Tröger's bases shows that the multiplicity of protons was generally oversimplified. The methylene protons of the benzylic and methanodiazocine units were reported as a doublet, thus ignoring the small, long-range couplings ( 4 J HH , 5 J HH , and 6 J HH ).…”

Chemistry of (E)‐2‐(2,4‐Dioxochroman‐3‐ylidene)‐2‐phenylacetonitrile: Access to Biscoumarin‐Fused Trioxabicycles

“…For instance, the well‐known Tröger's base ( 1 ) and its analogs have been used as chiral discriminators for the recognition of organic compounds (Figure 1). [1] Chromophore carrying analogs of the Tröger's base have displayed unique nonlinear optical properties, [2] and can be used as molecular switches [3] as well as liquid crystal dopants [4] . Further, coumarin‐fused oxazabicycle 2 was found to exhibit intriguing photochromism via a novel single‐electron transfer mechanism, [5] whereas coumarin‐fused oxazabicycle 3 was discovered to possess redox‐switching capability with emission variation as an output property (Figure 1).…”

“…Heterobicyclo [3,3,1]nonadiene represents an attractive molecular scaffold to organic chemists, mainly due to its derivatives possess various functional properties that can be applied to materials science and related fields. For instance, the wellknown Tröger's base (1) and its analogs have been used as chiral discriminators for the recognition of organic compounds (Figure 1).…”

Untitled

“…The rise of molecular machines [1,2] has inspired the fusion of photoresponsive units with the lambda-shape scaffold of Tröger base analogs (TBAs) that has resulted in the introduction of light-driven nanoswitches (ranging from 8 to 64 Å in length) [3]. Despite the long history and broad range applications of both TBAs [4] and azo switches [5], no azo carrying TBA was ever fashioned until 2016 [6].…”