TY - JOUR
T1 - Syntheses and structures of di(carboxylato)hexakis(acetonitrile)-dimolybdenum(II) bis(tetrafluoroborate) and trans-[di(μ-acetato)-di(acetonitrile)di(μ-bis(diphenylphosphino)amine) dimolybdenum (II)] bis(tetrafluoroborate)
AU - Cotton, F. Albert
AU - Kühn, Fritz E.
PY - 1996/11/1
Y1 - 1996/11/1
N2 - Di(carboxylato)hexakis(acetonitrile)dimolybdenum(II) bis(tetrafluoroborate) s, [Mo2(μ-O2CR)2(CH3CN) 6](BF4)2(R = CH3,CH2Cl, C(CH3)3, CF3) (3a-d), are easily accessible by reacting [Mo2(CH3CN)8](BF4)4 (2) with a stoichiometric amount or a slight excess of the appropriate carboxylic acid and anhydride in acetonitrile. A large excess of carboxylic acid leads to the formation of tetracarboxylates. As an example cis-[Mo2(μ-O2CCH2Cl)2(CH 3CN)6](BF4)2 (3b) has been structurally characterized. Crystallographic data are as follows: space group: I42d (No. 122), a = b = 10.733(2), c = 59.448(5) Å, V = 6848(2) Å3, Z = 8, d(Mo-Mo) = 2.140(1) Å. Trans-[Mo2(μ-O2CCH3)2(dppa) 2(CH3CN)2](BF4)2 (4) can be synthesized from cis-[Mo2(μ-O2CCH3)2(CH 3CN)6](BF4)2 (3a) and bis(diphenylphosphino)amine (dppa) at room temperature. This result contradicts earlier reports where bulky diphosphines such as dppm (sterically very similar to dppa) did not lead to bis-diphosphine products. Furthermore our results indicate that in all the syntheses reported to date for [Mo2(μ-O2CCH3)2(LL) 2](BF4)2 type-compounds [Mo2(μ-O2CCH3)2(CH 3CN)6](BF4)2 acts as the precursor compound. Crystallographic data for 4 are as follows: P21/c (No. 14), a = 19.683(3), b = 15.129(2), c = 21.084(1) Å, β = 101.30(1)°, V = 6848(2) Å3, Z = 4. There are two independent molecules of the cation in the unit cell, d(Mo-Mo) = 2.133(1) and 2.136(1) Å.
AB - Di(carboxylato)hexakis(acetonitrile)dimolybdenum(II) bis(tetrafluoroborate) s, [Mo2(μ-O2CR)2(CH3CN) 6](BF4)2(R = CH3,CH2Cl, C(CH3)3, CF3) (3a-d), are easily accessible by reacting [Mo2(CH3CN)8](BF4)4 (2) with a stoichiometric amount or a slight excess of the appropriate carboxylic acid and anhydride in acetonitrile. A large excess of carboxylic acid leads to the formation of tetracarboxylates. As an example cis-[Mo2(μ-O2CCH2Cl)2(CH 3CN)6](BF4)2 (3b) has been structurally characterized. Crystallographic data are as follows: space group: I42d (No. 122), a = b = 10.733(2), c = 59.448(5) Å, V = 6848(2) Å3, Z = 8, d(Mo-Mo) = 2.140(1) Å. Trans-[Mo2(μ-O2CCH3)2(dppa) 2(CH3CN)2](BF4)2 (4) can be synthesized from cis-[Mo2(μ-O2CCH3)2(CH 3CN)6](BF4)2 (3a) and bis(diphenylphosphino)amine (dppa) at room temperature. This result contradicts earlier reports where bulky diphosphines such as dppm (sterically very similar to dppa) did not lead to bis-diphosphine products. Furthermore our results indicate that in all the syntheses reported to date for [Mo2(μ-O2CCH3)2(LL) 2](BF4)2 type-compounds [Mo2(μ-O2CCH3)2(CH 3CN)6](BF4)2 acts as the precursor compound. Crystallographic data for 4 are as follows: P21/c (No. 14), a = 19.683(3), b = 15.129(2), c = 21.084(1) Å, β = 101.30(1)°, V = 6848(2) Å3, Z = 4. There are two independent molecules of the cation in the unit cell, d(Mo-Mo) = 2.133(1) and 2.136(1) Å.
KW - Crystal structures
KW - Dinuclear complexes
KW - Metal-metal bond complexes
KW - Molybdenum complexes
KW - Nitrile complexes
UR - http://www.scopus.com/inward/record.url?scp=0001159966&partnerID=8YFLogxK
U2 - 10.1016/s0020-1693(96)05320-0
DO - 10.1016/s0020-1693(96)05320-0
M3 - Article
AN - SCOPUS:0001159966
SN - 0020-1693
VL - 252
SP - 257
EP - 264
JO - Inorganica Chimica Acta
JF - Inorganica Chimica Acta
IS - 1-2
ER -