trans-rac-[1-Oxo-2-phenethyl-3-(2-thienyl)-1,2,3,4-tetrahydroisoquinolin-4-yl]methyl 4-methylbenzenesulfonate

The title compound, C29H27NO4S2, was synthesized by reaction of trans-rac-4-(hydroxymethyl)-2-phenethyl-3-(thiophen-2-yl)-3,4-dihydroisoquinolin-1(2H)-one and 4-methylbenzene-1-sulfonyl chloride in the presence of Et3N in CH2Cl2. The relative orientations of the benzene ring (A) of the 3,4-dihydroisoquinolinone ring system, the thiophene ring (B), the benzene ring (C) of the methylbenzene group and the phenyl ring (D) result in the following dihedral angles: A/B = 80.91 (16), A/C = 22.79 (18), A/D = 9.9 (2), B/C = 80.73 (19), B/D = 88.9 (2) and C/D = 29.9 (2)°. The crystal structure is stabilized by weak intermolecular C—H⋯O hydrogen bonds and C—H⋯π interactions.


Comment
The title compound, (I), was synthesized as part of a research project (Kandinska et al., 2006) seeking precursors for the production of new tetrahydroquinolone derivatives with biological activity (Rothweiler et al., 2008).
In the molecule of (I) (Fig.1), the benzene ring A (C10-C15) of 3,4-dihydroisoquinolinone ring system is essentially planar, with an r.m.s. deviation of 0.005 (3) Å for C11 and its other six-membered part is not planar [its Puckering parameters (Cremer & Pople, 1975)  An interesting feature of the crystal structure is the long C18-C19 bond of 1.594 (3) Å.
The crystal structure of (I) is stabilized by weak intra-and intermolecular C-H···O hydrogen bonds and C-H···π interactions (Table 1 and Fig. 2).

Refinement
The H atoms were positioned geometrically, with C-H = 0.93-0.97 Å, and refined using a riding model, with U iso (H) = 1.2 or 1.5U eq (C). The maximum diference peak and deepest difference hole are situated 0.13 Å from C19 and 0.36 Å from S2, respectively.
Figures Fig. 1. The molecular structure of (I), with 20% probability displacement ellipsoids for the non-hydrogen atoms.  Refinement. Refinement on F 2 for ALL reflections except those flagged by the user for potential systematic errors. Weighted Rfactors wR and all goodnesses of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The observed criterion of F 2 > σ(F 2 ) is used only for calculating -R-factor-obs etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.