Crystal structure of 1-(1-chloro­eth­yl)-6,7-dimeth­oxy-1,2,3,4-tetra­hydro­isoquinolinium chloride

Abstract

The title compound crystallizes in the monoclinic P2₁/c (No. 14) space group. The asymmetric unit of the crystal contains one independent mol­ecule with an 1R, 11R configuration of chiral carbon atoms.

1-(1-Chloro­eth­yl)-6,7-dimeth­oxy-1,2,3,4-tetra­hydro­iso­quinoline was synthesized through the reaction of homoveratryl­amine with racemic lactic acid. The formation of two enanti­omers, RR and SS, was detected by performing X-ray diffraction analysis on their chloride salts. The asymmetric unit of the crystal consists of a C₁₃H₁₉ClNO₂⁺ mol­ecular cation and a Cl⁻ anion. Two protonated enanti­omers of the title compound, with RR and SS configurations of the chiral atoms, are connected into hydrogen-bonded dimers bridged by Cl⁻ anions. Weak C—H⋯Cl inter­actions lead to the formation of a chain running along the a-axis direction of the unit cell, which corresponds to the longest dimension (the preferential growth direction) of the needle-shaped monocrystal. The crystal studied was refined as a two-component twin.