The molecular structures of (RS)‐1,2‐diphenylethyl methacrylate and (RS)‐α‐tert‐butylbenzyl methacrylate

Abstract

AbstractThe molecular structures of (RS)‐1,2‐diphenylethyl methacrylate (DPEMA) and (RS)‐α‐tert‐butylbenzyl methacrylate (t‐BBMA) were determined by means of X‐ray diffraction. Crystals of (RS)‐DPEMA are monoclinic, space group C2/c, a = 33,341(3), b = 5,916(1), c = 15,911(2) Å, β = 106,42(1)°, and Z = 8. Crystals of (RS)‐t‐BBMA are also monoclinic, space group P21/c, a = 6,028(1), b = 31,009(3), c = 15,207(1) Å, β = 96,780(8)°, and Z = 8. Both structures were solved by the direct method and refined by the block‐diagonal least‐squares procedure: DPEMA, R = 0,113 for 1 100 observed reflections and t‐BBMA, R = 0,081 for 2206 non‐zero reflections, respectively. The molecule of DPEMA has an antiperiplanar conformation as to the CC and CO double bonds about the C(1)C(2) bond, a synperiplanar conformation as to the CO and CO bond about the C(1)O(1) bond, and an anticlinal conformation about the O(1)C(5) bond. One of the two t‐BBMA molecules in an asymmetric unit has an antiperiplanar conformation as to the CC and CO double bonds about the C(1)C(2) bond, whereas the other antiperiplanar molecule may contain some synperiplanar conformation. Both molecules have a synperiplanar conformation as to the CO and CO bonds about the C(1)O(1) bond and an anticlinal conformation about the O(1)C(5).