1337985-51-9

Upstream product

• 99-96-7 4-hydroxy-benzoic acid 
• 2345-34-8 4-acetyloxy-benzoic acid 
• 27914-73-4 4-acetoxybenzoyl chloride 
• 652-67-5 Isosorbide 

Downstream Products

• 185756-31-4 (3R,3aS,6S,6aS)-hexahydrofuro[3,2-b]furan-3,6-bis(4-hydroxybenzoate) 
• 197663-64-2 1,4:3,6-dianhydro-D-sorbitol-2,5-bis(4-(4-methoxybenzoyloxy)benzoate) 
• 1337985-50-8 1,4:3,6-dianhydro-D-sorbitol-2,5-bis(4-(4-acetoxybenzoyloxy)benzoate) 
• 201794-01-6 1,4:3,6-dianhydro-D-sorbitol-2,5-bis(4-(4-(hexyloxy)benzoyloxy)benzoate) 

Relevant academic research and scientific papers

Bio-based chiral dopants having an isohexide skeleton for cholesteric liquid crystal materials

Chiral dopants were synthesized from bio-based epimeric isohexides (glucose-derived isosorbide and mannose-derived isomannide) and their phase transition behaviors and abilities for developing cholesteric liquid crystal (CLC) films were examined with a consideration of the core structure. In spite of lower reactivity of the endo hydroxy group of isomannide caused by the steric hindrance and intermolecular hydrogen bonding, final synthetic yields of chiral dopants bearing an isomannide core (64.5% for IH-2 and 65.0% for IH-4) did not show conspicuous difference compared with chiral dopants bearing isosorbide (68.4% for IH-1 and 74.0% for IH-3). On the other hand, in phase transition behaviors, chiral dopants bearing an isomannide core showed lower crystalline and melting temperatures than IH-1, IH-3 despite of the same substituents. The helical twisting power (HTP) of chiral dopants bearing isosorbide (IH-1 and IH-3) was higher than that of chiral dopants bearing isomannide (IH-2 and IH-4). The calculated HTPs of IH-1 and IH-3 were 26.6 and 42.1 μm-1, respectively. In the case of IH-3, the helical pitch length of CLC could be adjusted to reflect visible light by controlling its amount and showed best performance in the range 5.0 to 7.0 mol%. In contrast to IH-1 and IH-3, it was found that IH-2 and IH-4 could not induce CLC films that reflect visible light.

Tuning helical twisting power of isosorbide-based chiral dopants by chemical modifications

Isosorbide-based chiral dopants (ICD) with various substituent groups were newly synthesized to control their helical twisting powers (HTP). Phase transition behaviors of ICD molecules were first investigated by combined techniques of differential scanning calorimetry, wide-angle X-ray diffraction, and cross-polarized optical microscopy. ICD with n-hexyloxy end groups formed the multiple ordered phases, and those with methoxy or acetoxy end groups exhibited a simple crystal-to-isotropic transition. Energy-minimized chemical conformations of ICD molecules revealed that all the ICDs had twisted conformations and that the extension of the benzoyl ester moiety induced a higher twisted conformation. By varying substitution groups, HTPs of ICDs were controlled from 26.6 to 80.μm-1. Particularly, ICD with an acetoxy end group (ICD-2) showed the largest HTP. It was also realized that by controlling the content of ICD-2 from 3.0 to 4.5mol%, the helical pitch length of cholesteric LC mixture was adjusted to reflect a specific visible light. Copyright Taylor & Francis Group, LLC.