New branched chain tricycloquinazoline derivatives: a room temperature electron deficient discotic system

Abstract

Tricycloquinazoline (TCQ) based discotic liquid crystals have recently received increasing attention due to their interesting physical and electronic properties. Three new branched chain TCQ derivatives 6a–c were prepared and characterized. One of them, 6c, was found to be mesogenic at room temperature, having a very broad mesophase range. The small angle X-ray scattering of this compound shows a centre to centre distance of 3.29 Å, one of the lowest core–core separations known in discotic liquid crystal systems. This very close packing of the molecules in the column in conjunction with the stability of the mesophase well below and above the ambient temperature makes it very suitable for carrying out physical studies.

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