Quinoline unit

An original approach to assemblies of rotaxanes was suggested by Schalley et al. [56], The authors synthesized a rotaxane 40 containing the bis-quinoline unit in its wheel component. Subsequent exo-coordination of copper cations leads to a copper-bridged bis(rotaxane) 41 with perpendicularly oriented axles. 

A more elaborate sensor consists in a dendrimeric-like complex featuring eight quinoline units 132 (fig. 119, bottom), allowing the complexation of four Yb111 ions and yielding a 8.5-fold increase in the 980-nm emission upon thiocyanate complexation (Tsukube and Shinoda, 2006). 

C-C bond-forming reactions do not, however, always involve spirocyclic intermediates. The cyclopentadienyl product 111 is obtained during the depalladation of 110, derived from a thermally induced 1,3-H shift of its isomer 114. Here, PPhj plays a role similar to that of pyridine or maleic anhydride, in that it displaces the quinoline unit bound to palladium and, hence destabilizes the metallacyclic unit. The carbocyclic product 111 is assumedly formed as a result of an intramolecular C-H activation of the ri -bound olefin unit assisted by the proximity of the... 

Quinine (80) is a common quinoline derivative and an important antimalarial isolated from Cinchona bark (see Chapter 1 and compound number 1 in Section 1.1). Another antimalarial compound is Primaquine (81). Camptothecin (82) is an important anticancer drug that contains the quinoline unit. In all cases, the quinoline unit is highlighted in blue in the illustration. A typical isoquinoline derivative is papaverine (83), which is related to morphine and also isolated from the opium poppy. Papaverine relaxes smooth muscle tissue in blood vessels. Once again, the isoquinoline unit is highlighted. 

Polyquinolines having directly bonded quinoline units in the 6-positions and connected in the 2-positions by -phenylene units (eg. 5) are rigid rods that are highly crystalline, having crystalline transition temperatures at 500 C or above.These polymers are soluble only in the polymerization medium... 

In order to disrupt the crystal structure and improve solubility, longer pendent arms were placed in the 4-positions of the quinoline units. With an arm at least two phenylene units long, the crystal packing observed for 5 (x=2) could not be achieved, and a third phenyl... 

N.J. Parmar, H.A. Barad, B.M. Labana, R. Kant, V.K. Gupta, A glycerol mediated domino reaction an efficient, green synthesis of polyheterocycles incorporating a new thiochromeno[2,3-6]quinoline unit, RSC Adv. 3 (2013) 20719-20725. 

The copper complex derived from the ligand (402) that incorporates L-methionine and two quinoline units, each armed with a urea moiety, has been designed as a redox-reconfigurable catalyst for the Michael addition of ethyl malonate to / -nitrostyrene... 

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