Beilstein J. Org. Chem.2023,19, 700–718, doi:10.3762/bjoc.19.51
% yield via a gold/silver catalyst system (Scheme 27).
4 OxidativeC–Ccoupling
Whereas oxidativeC–Ccoupling precedes amination in the industrial route to 5H-dibenzo[b,f]azepine, oxidativeC–Ccoupling may also be the final step in the construction of the dibenzo[b,f]heteropine skeleton.
Comber and
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Graphical Abstract
Figure 1:
Dibenzo[b,f]azepine (1a), -oxepine (1b) and -thiepine (1c) as examples of dibenzo[b,f]heteropines (1...
Beilstein J. Org. Chem.2019,15, 727–732, doi:10.3762/bjoc.15.68
oxidativeC–Ccoupling of 2-nitrotoluenes (75–82% yield) and a reductive ring closure to form the diazocines (56–60% yield). The cyclization of the dinitro compound to the azo compound was improved in yield and reproducibility, by over-reduction to the hydrazine and reoxidation to the azo unit. In contrast
molecular switches in photo and mechanoresponsive macromolecules and other smart materials.
Keywords: bridged azobenzene; diazocine; mechanophor; oxidativeC–Ccoupling; photochrome; reductive azo cyclization; Introduction
The field of photoresponsive materials is of growing interest [1][2][3]. Several
step the hydroxy groups in 8a and 8b were protected as tert-butyl ethers (Scheme 2) to prevent oxidation in the following oxidativeC–Ccoupling [31]. The tert-butyl ether was chosen as the protecting group because it is stable towards the oxidizing conditions of the C–C coupling reactions and the
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Graphical Abstract
Figure 1:
(a) Isomerization of parent diazocine 1. Distances of carbon atoms para to the ethylene bridge were...