Esters of (S)-l,2-propanediol and (R,R)-2,3-butanediol — Chiral Compounds Inducing Cholesteric Phases with a Helix Inversion •
نویسندگان
چکیده
Mesogenic chiral esters of optically active (S)-l,2-propanediol and (R,R)-2,3-butanediol were synthesized. The compounds, added to a nematic phase induce cholesteric phases exhibiting a helix inversion with temperature variation. This effect is independent of the molecular structure of the nematic solvent. The inversion temperature varies only slightly with concentration but can be influenced by the mesogenic substituent.
منابع مشابه
Non-hydrogen-bonding-based, solvent-dependent helix inversion between pure P-helix and pure M-helix in poly(quinoxaline-2,3-diyl)s bearing chiral side chains.
Poly(quinoxaline-2,3-diyl)s bearing chiral (R)-2-butoxy side chains adopt pure right- or left-handed screw senses in CHCl(3) and 1,1,2-trichloroethane, respectively.
متن کاملA twist in chiral interaction between biological helices
Using an exact solution for the pair interaction potential, we show that long, rigid, chiral molecules with helical surface charge patterns have a preferential interaxial angle ~ RH L where L is the length of the molecules, R is the closest distance between their axes, and H is the helical pitch. Estimates based on this formula suggest a solution for the puzzle of small interaxial angles in α-h...
متن کاملTwist in chiral interaction between biological helices.
Using an exact solution for the pair interaction potential, we show that long, rigid, chiral molecules with helical surface charge patterns have a preferential interaxial angle approximately sqrt[RH]/L, where L is the length of the molecules, R is the closest distance between their axes, and H is the helical pitch. Estimates based on this formula suggest a solution for the puzzle of small inter...
متن کاملThe metabolism of acetone in rat.
Intraperitoneal injection of 5 mumol of acetone/g, body weight, into 3 rats previously fed 1% acetone (v/v) in their drinking water resulted in the appearance in blood serum of 16 +/- 2 nmol of 1,2-propanediol/ml and 8 +/- 1 nmol of 2,3-butanediol/ml. No detectable 1,2-propanediol or 2,3-butanediol was found in the serum of animals after acetone or saline injection without prior addition of ace...
متن کاملPressure-dependent helix inversion of poly(quinoxaline-2,3-diyl)s containing chiral side chains in non-aqueous solvents.
Poly(quinoxaline-2,3-diyl)s with chiral (S)-2-butoxymethyl side chains dissolved in 1,2-dichloroethane experience a reversible pressure-dependent helix inversion from P- to M-helical structures between 0.1 MPa and 200 MPa.
متن کامل