3-Benzylidene-8-methoxy-6-(prop-2-enyl)chroman-4-one

Abstract

Key indicators: single-crystal X-ray study; T = 150 K; mean (C-C) = 0.002 Å; R factor = 0.045; wR factor = 0.129; data-to-parameter ratio = 21.4.

Structural studies of seven homoisoflavonoids, six thiohomoisoflavonoids, and four structurally related compounds

“…The dihedral angle C8a-O1-C2-C3 (Fig. 1, Table 4) is rather close to ±50°in all molecules of IIIa-IIId and have rather similar angle values in previously known derivatives (38°-54°) [35][36][37][38][39][40][41][42][43][44]. The positive or negative angles show that C2 is on the left (?)…”

“…3-Benzylidene-8-methoxy-6-methylchroman-4-one [39] shows also similar value of 59.67(4)°. In IIIb-IIId these values are slightly smaller (46°-55°) as also in several 3-benzylidene-4-chromanone derivatives [37,38,[40][41][42][43][44]. 3-Benzylidene-6-methoxychroman-4-one [36] shows value of 67.78(3)°f or this angle and is the only one significantly larger.…”

“…Small static disorder was found to occur in the case of C3 and C2a, but the solving of it was not successful without using strong positional and anisotropic constraints and it was not resolved in the least squares refinement. The angle between the planes of two aromatic rings (Table 5) is smaller than in V but larger than in IIIa-IIId and most of the related 3-benzylidene-4-chromanone structures [35][36][37][38][39][40][41][42][43][44]. Three known 2-benzyl-1-tetralone derivatives [48][49][50] show larger inclination angles (74°-80°) between aromatic planes, but slightly smaller twist of the molecule end, according to C8a-C1-C2-C2a dihedral angles (162°-168°).…”

“…The crystal structure of (E)-3-benzylidene-4-chromanone was published in 1987 by Katrusiak et al [35] and our structural search showed that since then nine substituted derivatives [36][37][38][39][40][41][42][43][44] of it have been added to Cambridge Structural Database (CSD) [45]. The crystallographic diagrams for four new derivatives IIIa-IIId are presented in Fig.…”

3-Benzylidene-8-methoxy-6-methylchroman-4-one

“…For related literature, see: Puviarasan et al (1998); Tillekeratne et al (2001); Nissa et al (2001); Kang et al (2004); Wu, Xu, Zhou et al (2005); Wu, Xu, Wan et al (2005); Schollmeyer et al (2005). A similar methoxychroman-4-one compound has been reported recently (Suresh et al, 2007). Table 1 Hydrogen-bond geometry (Å , ).…”