CH/π Interactions Implicated in the Crystal Structure of Transition Metal Compounds − A Database Study

Abstract

A statistical study was carried out to investigate the role of the CH/π interaction in the crystal structure of transition metal compounds. Thus, short CH/π distances were surveyed in crystal structures deposited in the Cambridge Structural Database. Among organometallic entries bearing C 6 or C 5 aromatic rings, a substantial part of the structures has been found to have intermolecular CH/π contacts shorter than the van der Waals distance. Further, in many structures short intramolecular CH/π contacts have been found. Interligand and intraligand CH/π interactions were also surveyed in co-

N-Benzyl-N-phosphino-tert-butylsulfinamide and Its Coordination Modes with Ir(I), Cu(I), Pd(II), and Pt(II): P,S or P,O?

“…Inspection of the crystal structure of 6 highlighted that both electrostatic repulsion (between oxygen and chlorine atom) and steric hindrance force the phenyl ring of the benzyl group close to the allyl ligand (Figure ). Indeed, the anti -H(26A) proton is located at a short distance, viz., 2.795 Å, from the centroid Q1 of the [(C18), C(19), C(20), C(21), C(22), C(23)] and closer to the C19 and C20 atoms with lengths 2.859 and 2.955 Å, respectively . The CH/π distance fits the usual range in complexes featuring intramolecular sp 2 -CH···π Ph (2.83 ± 0.16 Å) and is comparable to that reported by Scrivanti (2.66 and 2.83 Å). , This is a rare example of an intramolecular CH/π interaction involving a terminal hydrogen atom of an allyl ligand in neutral palladium(II) complexes.…”

“…50 The PtÀCl(1) bond distance (2.361 Å) trans to the phosphorus ligand is significantly longer than the PtÀCl(2) distance trans to sulfur (2.314 Å) (see Table 4). The PtÀCl(2) bond length in complex 8 is consistent with the average bond length of Organometallics ARTICLE 2.323 (38) Å reported by Orpen for various platinum complexes. 51 The PtÀCl(1) (2.361 Å) bond length is consistent with the low trans effect of chlorine.…”

N-Benzyl-N-phosphino-tert-butylsulfinamide and Its Coordination Modes with Ir(I), Cu(I), Pd(II), and Pt(II): P,S or P,O?

“…Inspection of the crystal structure of 6 highlighted that both electrostatic repulsion (between oxygen and chlorine atom) and steric hindrance force the phenyl ring of the benzyl group close to the allyl ligand (Figure ). Indeed, the anti -H(26A) proton is located at a short distance, viz., 2.795 Å, from the centroid Q1 of the [(C18), C(19), C(20), C(21), C(22), C(23)] and closer to the C19 and C20 atoms with lengths 2.859 and 2.955 Å, respectively . The CH/π distance fits the usual range in complexes featuring intramolecular sp 2 -CH···π Ph (2.83 ± 0.16 Å) and is comparable to that reported by Scrivanti (2.66 and 2.83 Å). , This is a rare example of an intramolecular CH/π interaction involving a terminal hydrogen atom of an allyl ligand in neutral palladium(II) complexes.…”

“…50 The PtÀCl(1) bond distance (2.361 Å) trans to the phosphorus ligand is significantly longer than the PtÀCl(2) distance trans to sulfur (2.314 Å) (see Table 4). The PtÀCl(2) bond length in complex 8 is consistent with the average bond length of Organometallics ARTICLE 2.323 (38) Å reported by Orpen for various platinum complexes. 51 The PtÀCl(1) (2.361 Å) bond length is consistent with the low trans effect of chlorine.…”

Sterically Demanding Phosphines with 2,6-Dibenzhydryl-4-methylphenyl Core: Synthesis of Ru II , Pd II , and Pt II Complexes, and Structural and Catalytic Studies

“…The analogous arene complexes 5 and 6 have slightly longer C–H···π interactions between the methine hydrogen of the benzhydryl group and with the ipso carbon of one of the phenyl rings of the PPh 2 group (H8···C34 = 2.88 Å in 5 , H8···C34 = 2.88 Å, and H21···C40 = 2.83 Å in 6 ) (see Figure ). The C–H···π interactions found in these complexes are very comparable to the same in analogous complexes reported in the literature. , NMR spectroscopy is a powerful method for studying the weak interactions in solution; the 1 H– 1 H NOESY experiments are very useful for the detection of C–H···π interactions in solutions . Two-dimensional nuclear magnetic resonance (2-D) NMR ( 1 H– 1 H COSY and 1 H– 1 H NOESY) and NOE experiments were carried out in order to gain some insight into the C–H···π interactions.…”

Pt4S4 Clusters with Functionalized Thiosemicarbazones derived from 5‐Acetylbarbituric Acid

“…The planes in question are apart by 3.259(1)Ϫ3.307(1) Å and 3.215(1)Ϫ3.247(1) Å , respectively. These parameters are consistent with the existence of antiparallel intramolecular π-π stacking, as described by Janiak in copper(II) compounds with heterocyclic nitrogen ligands [26,27].…”

N-Benzyl-N-phosphino-tert-butylsulfinamide and Its Coordination Modes with Ir(I), Cu(I), Pd(II), and Pt(II): P,S or P,O?

“…Inspection of the crystal structure of 6 highlighted that both electrostatic repulsion (between oxygen and chlorine atom) and steric hindrance force the phenyl ring of the benzyl group close to the allyl ligand (Figure ). Indeed, the anti -H(26A) proton is located at a short distance, viz., 2.795 Å, from the centroid Q1 of the [(C18), C(19), C(20), C(21), C(22), C(23)] and closer to the C19 and C20 atoms with lengths 2.859 and 2.955 Å, respectively . The CH/π distance fits the usual range in complexes featuring intramolecular sp 2 -CH···π Ph (2.83 ± 0.16 Å) and is comparable to that reported by Scrivanti (2.66 and 2.83 Å). , This is a rare example of an intramolecular CH/π interaction involving a terminal hydrogen atom of an allyl ligand in neutral palladium(II) complexes.…”

“…50 The PtÀCl(1) bond distance (2.361 Å) trans to the phosphorus ligand is significantly longer than the PtÀCl(2) distance trans to sulfur (2.314 Å) (see Table 4). The PtÀCl(2) bond length in complex 8 is consistent with the average bond length of Organometallics ARTICLE 2.323 (38) Å reported by Orpen for various platinum complexes. 51 The PtÀCl(1) (2.361 Å) bond length is consistent with the low trans effect of chlorine.…”

Sterically Demanding Phosphines with 2,6-Dibenzhydryl-4-methylphenyl Core: Synthesis of Ru II , Pd II , and Pt II Complexes, and Structural and Catalytic Studies

“…The analogous arene complexes 5 and 6 have slightly longer C–H···π interactions between the methine hydrogen of the benzhydryl group and with the ipso carbon of one of the phenyl rings of the PPh 2 group (H8···C34 = 2.88 Å in 5 , H8···C34 = 2.88 Å, and H21···C40 = 2.83 Å in 6 ) (see Figure ). The C–H···π interactions found in these complexes are very comparable to the same in analogous complexes reported in the literature. , NMR spectroscopy is a powerful method for studying the weak interactions in solution; the 1 H– 1 H NOESY experiments are very useful for the detection of C–H···π interactions in solutions . Two-dimensional nuclear magnetic resonance (2-D) NMR ( 1 H– 1 H COSY and 1 H– 1 H NOESY) and NOE experiments were carried out in order to gain some insight into the C–H···π interactions.…”

Pt4S4 Clusters with Functionalized Thiosemicarbazones derived from 5‐Acetylbarbituric Acid

“…The planes in question are apart by 3.259(1)Ϫ3.307(1) Å and 3.215(1)Ϫ3.247(1) Å , respectively. These parameters are consistent with the existence of antiparallel intramolecular π-π stacking, as described by Janiak in copper(II) compounds with heterocyclic nitrogen ligands [26,27].…”

N-Benzyl-N-phosphino-tert-butylsulfinamide and Its Coordination Modes with Ir(I), Cu(I), Pd(II), and Pt(II): P,S or P,O?

“…Inspection of the crystal structure of 6 highlighted that both electrostatic repulsion (between oxygen and chlorine atom) and steric hindrance force the phenyl ring of the benzyl group close to the allyl ligand (Figure ). Indeed, the anti -H(26A) proton is located at a short distance, viz., 2.795 Å, from the centroid Q1 of the [(C18), C(19), C(20), C(21), C(22), C(23)] and closer to the C19 and C20 atoms with lengths 2.859 and 2.955 Å, respectively . The CH/π distance fits the usual range in complexes featuring intramolecular sp 2 -CH···π Ph (2.83 ± 0.16 Å) and is comparable to that reported by Scrivanti (2.66 and 2.83 Å). , This is a rare example of an intramolecular CH/π interaction involving a terminal hydrogen atom of an allyl ligand in neutral palladium(II) complexes.…”

“…50 The PtÀCl(1) bond distance (2.361 Å) trans to the phosphorus ligand is significantly longer than the PtÀCl(2) distance trans to sulfur (2.314 Å) (see Table 4). The PtÀCl(2) bond length in complex 8 is consistent with the average bond length of Organometallics ARTICLE 2.323 (38) Å reported by Orpen for various platinum complexes. 51 The PtÀCl(1) (2.361 Å) bond length is consistent with the low trans effect of chlorine.…”

Sterically Demanding Phosphines with 2,6-Dibenzhydryl-4-methylphenyl Core: Synthesis of Ru II , Pd II , and Pt II Complexes, and Structural and Catalytic Studies

“…The analogous arene complexes 5 and 6 have slightly longer C–H···π interactions between the methine hydrogen of the benzhydryl group and with the ipso carbon of one of the phenyl rings of the PPh 2 group (H8···C34 = 2.88 Å in 5 , H8···C34 = 2.88 Å, and H21···C40 = 2.83 Å in 6 ) (see Figure ). The C–H···π interactions found in these complexes are very comparable to the same in analogous complexes reported in the literature. , NMR spectroscopy is a powerful method for studying the weak interactions in solution; the 1 H– 1 H NOESY experiments are very useful for the detection of C–H···π interactions in solutions . Two-dimensional nuclear magnetic resonance (2-D) NMR ( 1 H– 1 H COSY and 1 H– 1 H NOESY) and NOE experiments were carried out in order to gain some insight into the C–H···π interactions.…”

Pt4S4 Clusters with Functionalized Thiosemicarbazones derived from 5‐Acetylbarbituric Acid

“…The planes in question are apart by 3.259(1)Ϫ3.307(1) Å and 3.215(1)Ϫ3.247(1) Å , respectively. These parameters are consistent with the existence of antiparallel intramolecular π-π stacking, as described by Janiak in copper(II) compounds with heterocyclic nitrogen ligands [26,27].…”