ISSN:
0025-116X
Schlagwort(e):
Chemistry
;
Polymer and Materials Science
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
,
Physik
Notizen:
The 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).
Zusätzliches Material:
6 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/macp.1984.021850508
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