3-Benzylidene-8-methoxy-6-(prop-1-enyl)chroman-4-one

Abstract

Key indicators: single-crystal X-ray study; T = 150 K; mean (C-C) = 0.005 Å; R factor = 0.068; wR factor = 0.183; data-to-parameter ratio = 15.1.In the title compound, C 20 H 18 O 3 , the phenyl ring makes a dihedral angle of 50.41 (10) with the benzene ring of the chromanone unit. The molecular structure is stabilized by weak intramolecular C-HÁ Á ÁO interactions and the crystal packing is stabilized by weak intermolecular C-HÁ Á ÁO interactions. ExperimentalCrystal data C 20 H 18 O 3 M r = 306.34 Monoclinic, P2 1 =c a = 10.0763 (8) Å b = 6.9018 (7) Å c = 22.1841 (18) Å = 98.690 (7) V = 1525.1 (2) Å 3 Z = 4 Mo K radiation = 0.09 mm À1 T = 150 (2) K 0.18 Â 0.11 Â 0.06 mm Data collection Stoe IPDS 2 diffractometer Absorption correction: integration (X-RED32; Stoe & Cie, 2002) T min = 0.984, T max = 0.995 11793 measured reflections 3177 independent reflections 1494 reflections with I > 2(I) R int = 0.133 Refinement R[F 2 > 2(F 2 )] = 0.068 wR(F 2 ) = 0.183 S = 0.92 3177 reflections 210 parameters H-atom parameters constrained Á max = 0.21 e Å À3

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.…”

8-Methoxy-3-(4-methylbenzylidene)-6-(prop-1-enyl)chroman-4-one

“…For related lituerature, see: Puviarasan et al (1998); Tillekeratne et al (2001); Nissa et al (2001); Kang et al (2004); Wu, Xu, Wan et al (2005); Wu, Xu, Zhou et al (2005); Schollmeyer et al (2005); Suresh et al (2007).…”