Anthony KERMAGORET - THESES ET MEMOIRES DE L'UDS

N2-Ni1-Cl1 169.45(12) 89.35(15)
N2-Ni1-Cl1′ 90.48(12) 169.36(13)
O3-Ni1-Cl1 92.57(12) 93.41(13)
O3-Ni1-Cl1′ 93.51(12) 95.95(15)
Cl1-Ni1-Cl1′ 86.84(8) 85.48(5)
Ni1-Cl1-Ni1 93.16(8) 93.90(5)
N2-Ni1-O3 77.40(18) 77.87(19)
O1-C1-C2 106.3(4) 109.1(6)
C1-C2-N1 123.1(5) 116.8(6)
C2-N1-Ni1 114.0(4) 115.8(4)
Ni1-O3-C7 113.8(4) 113.7(4)
O3-C7-C8 106.4(5) 109.6(7)
C7-C8-N2 123.3(5) 115.9(6)
C8-N2-Ni1 113.6(4) 116.1(4)
Chapitre II
The dications in 14·C6H12 and in 15·3CH2Cl2 form centrosymmetric dimers and their Ni(II)
centres adopt a distorted octahedral coordination geometry, very similar to those of 11 and 12
which contain gem-dimethyl substituents in α-position to the OH donor. 54 Each Ni(II) is
surrounded by two N,O chelates, whose N and OH donor groups are cis and trans to each
other, respectively, and by two bridging chlorides which are trans to the nitrogen atoms. The
crystal structure of 15·3CH2Cl2 revealed two independent but almost identical molecules in
the unit cell. In both 14 and 15, the two chloride counter anions do not interact with the metal
centres and are at 4.702(3) and 4.713(3) Å for 14 and 4.535(2) and 4.552(2) Å for 15 from a
Ni(II) centre. However, interactions between the chloride counter anions and the hydrogen
atoms of the OH functions are observed, with O1-H1···Cl2 and O3’-H3’···Cl2 distances of
2.984(4) and 2.994(4) Å (Table S1†), for 14 and 2.993(4) and 2.972(5) Å (Table S2†), for 15,
respectively (calculated O1-H1···Cl2 and O3’-H3’···Cl2 angles of 158 and 158 ° for 14 (Table
S1†) and 157 and 162 °, for 15, respectively (Table S2†). As shown by the O1-Ni-O2 angle
of 171.7(2)° for 14·C6H12 against 168.2(2)° for 11, the metal centre in 14·C6H12 has a
coordination geometry less distorted than in 11. Compared to 11, 14·C6H12 presents slightly
shorter Ni-N and Ni-Cl distances.
Complex 15 has similar structural characteristics to 12 and these will therefore not be
discussed in detail. The structure of a nickel complex coordinated by two (pyridin-2-
yl)methanol ligands has been described recently but the coordination of two water molecules
led instead to a mononuclear structure with an octahedral nickel centre. 56
Complex 15 has been obtained recently in a less convenient way by reaction of the
phosphinitopyridine ligand 16 with NiCl2 in MeOH. This reaction led to the cleavage of the
P-O bond and formation of 15 and [NiCl2(PPh2OMe)2] [eqn (4)]. 57
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