1,4-Bis(iodomethyl)benzene

Abstract

The centrosymmetric title compound, C8H8I2, was prepared by metathesis from the dibromo analogue. In the crystal structure, weak C—H⋯I inter­actions link the mol­ecules into stacks down the b axis. The structure is further stabilized by short I⋯I contacts [3.8433 (2) Å], forming undulating sheets in the (101) plane.

Crystal structures of two bis(iodomethyl)benzene derivatives: similarities and differences in the crystal packing

“…For each molecule the C-I bonds of the substituents point away from opposite faces of the benzene rings with the C-C-I planes almost orthogonal to the ring planes; dihedral angles = 87.99 (14) for (I) and 82.23 (14) and 83.61 (15) for (II). The C1-C11 and C11-I1 bond lengths in (I) and C1-C11, C11-I1, C3-C31 and C31-I3 in (II) are reasonably self-consistent and also compare well with those found in the isomeric 1,4bis(iodomethyl)benzene (McAdam et al 2009).…”

“…For example I1Á Á ÁI3 = 3.8662 (2) Å for (II) but the equivalent BrÁ Á ÁBr distance is 3.6742 (3) Å for the meta-dibromo analogue (Jones & Kus, 2007). Similar isostructural behaviour is observed for para-bis(iodomethyl)benzene (McAdam et al, 2009) and its dibromo analogue (Jones & Kus, 2007). However, in contrast, despite (I) and the ortho-dibromo analogue both displaying twofold symmetry, compound (I) crystallizes in the monoclinic space group C2/c while that for Overall packing for (II) viewed along the b-axis direction.…”

“…A search of the Cambridge Structural Database (Version 5.36 with three updates; Groom & Allen, 2014) for molecules incorporating a C 6 CH 2 I fragment surprisingly generated only five hits for iodomethylbenzene derivatives. One of these is the isomeric 1,4-bis(iodomethyl)benzene reported by us previously (McAdam et al, 2009), while two others are the organic compounds 2-(iodomethyl)-1,3,5-trimethylbenzene (Bats, 2014) and 3 0 -iodo-5 0 -(iodomethyl)biphenyl-4-carbonitrile (He et al, 2013). The other two entries are metal complexes (Martínez-García et al, 2010;Rivada-Wheelaghan et al, 2012).…”

σ-Hole⋯π and lone pair⋯π interactions in benzylic halides

“…As an example, no halogen bonds are observed in the crystal structure of 1,4-bis(iodomethyl)benzene. 43 Moreover, the I⋯phenyl distance observed in 1 is one of the shortest described to date and only in one single case a shorter contact (3.58 Å) has been reported. 44 The situation observed in benzylic bromides is very similar.…”

“…C NMR (CDCl 3 , 75 MHz): δ = 160.6 (d, J = 248.0 Hz), 129.7 (d, J = 7.9 Hz), 128.9 (d, J = 5.0 Hz), 128.5 (d, J = 13.2 Hz), 124.0 (d, J = 3.1 Hz), 116.6 (d, J = 23.0 Hz), 78.3, 45.1 (d, J = 8.1 Hz), 44.9, 29.1, 28.0, 27.1, 27.0 ppm; MS (EI, 70 eV) m/z (%): 226, (3) [M + + 2], 224 (9) [M + ], 189 (95), 156(43), 147(66), 133 (49), 109(58), 67 (100); Elemental analysis (%) calc. for C 13 H 14 FCl: C 69.49, H 6.28; found: C 69.38, H 8.73.…”