Crystal and molecular structure of Mn [ (OPPh2) 2N] 3 · CH2Cl2, a new monomeric manganese (III) complex stabilized by oxygen chelating ligands

Article abstract of DOI:10.1016/S0277-5387(98)00030-8

The reaction between [Mn (CO) ₅] Br and Na [ (OPPh₂) ₂N] in argon atmosphere affords the preparation of Mn (CO) ₄ [ (OPPh₂) ₂N] as a white powder. During attempts to grow X-ray diffraction quality crystals the tetracarbonylmanaganese (I) complex was oxidized and deep purplish-blue crystals were isolated. An X-ray diffractometry analysis has revealed the identity of the new product, i.e. the manganese (III) derivative, Mn [ (OPPh₂) ₂N] ₃ · CH₂Cl₂. The compound crystallizes in the triclinic space group P-1 and the crystal contains discrete, monomeric molecules of Mn [ (OPPh₂) ₂N] ₃. The imidodiphosphinato groups are coordinated through both oxygen atoms of a ligand moiety to the central manganese atom. The resulted coordination octahedron exhibits a tetragonally elongated distortion as reflected by the Mn - O bond lengths [av. 2.130 (16) , 1.945 (6) A] and cis O - Mn - O bond angles [endocyclic (av.) 90.5 (0.6) ° ; exocyclic (range) 87.2 (0.1) -92.7 (0.1) °] . The structure of the title compound is compared with those of other monomeric manganese (III) derivatives containing MnO₆ cores with various degrees of distortion.

Full text of DOI:10.1016/S0277-5387(98)00030-8

Polyhedron Vol[ 06\ No[ 05\ pp[ 1568Ð1574\ 0887
Þ 0887 Elsevier Science Ltd
Pergamon
All rights reserved[ Printed in Great Britain
9166Ð4276:87 ,08[99¦9[99
\
PII ] S9166Ð4276"87#99929Ð7
Crystal and molecular structure of
Mnð"OPPh1#1NŁ2 = CH1Cl1\ a new monomeric
manganese"III# complex stabilized by oxygen
chelating ligands
Noe Zuniga!Villareal\ꢀa Marisol Reyes Lezama\a Simon Hernandez!Ortegaa
ꢁ
and Cristian Silvestrub
a Instituto de Qu(mica\ Universidad Nacional Autonoma de Mexico\ Ciudad Universitaria\ Coyoacan\
ꢁ
ꢁ
ꢁ
ꢁ
93409 Mexico\ D[F[\ Mexico
ꢁ
b Facultatea de Chimie\ Universitatea {{Babesž!Bolyai||\ RO!2399 Cluj!Napoca\ Roumania
"Received 19 October 0886 ^ accepted 01 January 0887#
Abstract*The reaction between ðMn"CO#4ŁBr and Nað"OPPh1#1NŁ in argon atmosphere a}ords the prep!
aration of Mn"CO#3ð"OPPh1#1NŁ as a white powder[ During attempts to grow X!ray di}raction quality crystals
the tetracarbonylmanaganese"I# complex was oxidized and deep purplish!blue crystals were isolated[ An X!
ray di}ractometry analysis has revealed the identity of the new product\ i[e[ the manganese"III# derivative\
Mnð"OPPh1#1NŁ2 = CH1Cl1[ The compound crystallizes in the triclinic space group P!0 and the crystal contains
discrete\ monomeric molecules of Mnð"OPPh1#1NŁ2[ The imidodiphosphinato groups are coordinated through
both oxygen atoms of a ligand moiety to the central manganese atom[ The resulted coordination octahedron
exhibits a tetragonally elongated distortion as re~ected by the Mn0O bond lengths ðav[ 1[029"05#\ 0[834"5#
AýŁ and cis O0Mn0O bond angles ðendocyclic "av[# 89[4"9[5#> ^ exocyclic "range# 76[1"9[0#Ð81[6"9[0#>Ł[ The
structure of the title compound is compared with those of other monomeric manganese"III# derivatives
containing MnO5 cores with various degrees of distortion[ Þ 0887 Elsevier Science Ltd[ All rights reserved
Keywords] manganese"III# complexes ^ imidodiphosphinato[
———————————————————————————————————————————————
Recently we have described the synthesis and the bit a tetrahedral NiS3 core\ Nið"SPMe1#"SPPh1#NŁ1\
molecular structure of the monomeric complex has a square!planar NiS3 core ð7Ł\ while the dinuclear
Mn"CO#3ð"SPPh1#1NŁ ð0Ł[ Our interest in the inves! "Ni1ð"OPPh1#1NŁ3"H1O## contains two di}erent octa!
tigation of metal complexes containing such ligands hedral NiO5 cores ð8Ł[
prompted us to attempt the preparation of the dioxo
We wish to report here the molecular structure of
analog in order to establish structural changes which the manganese"III# complex\ Mnð"OPPh1#1NŁ2 =
might be produced by changes in the chalcogen atoms CH1Cl1\ produced via aerial oxidation during recrys!
attached to phosphorus[ Several previous studies tallization of the product isolated by reacting
using phosphorus ligands have proved that modi! ðMn"CO#4ŁBr and Nað"OPPh1#1NŁ[ It should be noted
_cation in the organic groups or chalcogen atoms at that the oxygen!donor ligands are known to stabilize
phosphorus may result in dramatic structural changes manganese"III# species ð09Ł[
ð1Ł not only in the case of Main Group metal com!
pounds ðe[g[ lead compounds\ Pb"S1PR1#1 ð2\3Ł\ inor!
EXPERIMENTAL
ganic and organoantimony"III# and antimony"V#
compounds ð4Ł\ but also for transition metal com!
pounds ðe[g[ Nið"SPR1#1NŁ1\ R ꢂ Me ð5Ł\ Ph ð6\7Ł exhi!
ðMn"CO#4ŁBr ð00Ł was obtained according to litera!
ture[ IR spectra were obtained in KBr disk "3999Ð199
cm−0# using a PerkinÐElmer 172B spectrometer[ H\
0
ꢀ Author to whom correspondence should be addressed[
02C and 20P NMR spectra were recorded using Varian
1568

1579
N[ Zuniga!Villareal et al[
Gemini 199 and Varian VXR 299S instruments[ The "KBr\ cm−0# ] nas"P1N# 0132 vs ^ n"PO# 0015 vs\ 0986
chemical shifts are reported in ppm relative to TMS s ^ n"CO# 1924 vs\ 1997 vs\ 0872 vs\ 0813 vs[
and H2PO3 74)\ respectively[
X!ray crystal determination of Mnð"OPPh1#1NŁ2
Preparation of tetraphenylimidodiphosphinic acid\
Empirical formula C61H59N2O5P5Mn=CH1Cl1\
"OPPh1#1HN ð01Ł
M ꢂ 0277[8\ triclinic\ a ꢂ 02[461"0#\ b ꢂ 02[741"0#\
c ꢂ 07[650"1#
_\
a ꢂ 84[33"1#\
b ꢂ 87[49"1#\
A slight excess of H1O1 29) "03 ml# was added
dropwise to a suspension of "PPh1#1NH "19 g\ 9[94
mol# in 199 ml THF\ and the reaction mixture was
stirred over night[ The resulting white\ solid product
was _ltered\ washed with THF and dried in air[ Yield ]
10 g "86)#\ m[p[ ꢂ 164Ð166>C "lit[ ð01Ł 157Ð158>C#[
IR "KBr\ cm−0# ] n"PO# 0019 s\ 0094 s ^ nas"P1NH# 819
g ꢂ 86[97"1#>\ U ꢂ 2327[6"4# _2\ F"999# ꢂ 0325\
Z ꢂ 1\ DC ꢂ 0[230 g cm−2\ space group P!0\ m"CuÐ
Ka# ꢂ 3[920 mm−0\ crystal size 9[17×9[15×9[13 mm[
Purplish blue prisms of Mnð"OPPh1#1NŁ2[ ðAnal[
Calc[ for C61H59N2O5P5Mn=CH1Cl1 ] C\ 52[0 ^ H\ 3[4 ^
N\ 2[9 ^ Found ] C\ 51[7 ^ H\ 3[3 ^ N\ 1[7) ^ ES "CH1Cl1\
cm−0# ] 21\469\ 07\149Ł were obtained from CH1Cl1:n!
hexane solution[ Data were collected at room tem!
perature "182 K# on a Siemens P3:PC four!circle
di}ractometer with parallel!graphite crystal mono!
chromator "CuÐKa radiation\ l ꢂ 0[43067 _#\ for
8559 re~ections of which 8083 were independent
re~ections ðRint ꢂ 5[19)Ł and 6176 "F1 × 1[9s"F1##
were used in the full!matrix least!squares re_nement
with the SHELXL!86 program system ð03Ł[ The struc!
ture was solved by Patterson methods ð04Ł and di}er!
ence Fourier synthesis revealed the positions for the
other non!hydrogen atoms[ All non!hydrogen atoms
were re_ned anisotropically\ and hydrogen atoms
were calculated as a riding model with isotropic U[
Semi!empirical absorption correction was applied
based on c!scan "transmission ] min[ 9[9017\ max[
9[6534#[ The CH1Cl1 solvent molecule was distorted
and was modeled ð03Ł in two positions for each atom ^
the site occupation factors were 9[29:9[69 for
C"0a#:C"0b#\ Cl"0#:Cl"0a# and Cl"1#:Cl"1a#\ respec!
tively[ The _nal R values are R0 ꢂ S=Fo−Fc=:=S=Fo= ꢂ
5[13) and wR1ꢂðS"w=Fo−Fc=#1:Sw=F9=1Ł0:1ꢂ04[72)
0
s[ H NMR "CDCl2\ 199 MHz# ] 6[24 m "2H\ C5H4!
meta¦para#\ 6[79 ddd ð1H\ C5H4!ortho\ 2J"PH# 01[7\
3
2J"HH# 6[4\ J"HH# 0[4 HzŁ[ 02C NMR "CDCl2\ 49
MHz# ] 017[13 m ðCm\ 2J"PC# 02[9 HzŁ\ 020[85 s "Cp#\
1
0
020[85 m ðCo\ J"PC# 09[8 HzŁ\ 023[22 d ðCi\ J"PC#
090[5 HzŁ[ 20P NMR "CDCl2\ 010[3 MHz# ] 08[3 s[
Preparation of sodium tetraphenylimidodiphosphinate\
Nað"OPPh1#1NŁ ð02Ł
"OPPh1#1NH "3[4 g\ 09[7 mmol# and NaOMe "9[5
g\ 00 mmol# in 099 ml ethanol were stirred for 5 h\ at
room temperature[ The insoluble solid product was
_ltered\ and the solvent was removed from the clear
_ltrate in a rotary evaporator to dryness[ The remain!
ing white solid was extracted several times in a Soxhlet
apparatus using MeCN as solvent[ The white crystals
of the title compound which deposited from the
MeCN extract were _ltered and dried in vacuo[ Yield ]
2[2 g "69)#\ m[p[ ꢂ 224Ð227>C[ IR "KBr\ cm−0# ]
nas"P1N# 0159 vs\ 0119 vs ^ n"PO# 0039 vs\ 0019 s[
0H NMR "CD2OD\ 299 MHz# ] 6[07 m "2H\ C5H4!
meta¦para#\ 6[61 ddd "1H\ C5H4!ortho\ 2J"PH# 01[2\
2J"HH# 6[6\ 3J"HH# 0[8#[ 02C NMR "CD2OD\ 64
MHz# ] 017[41 m ðCm\ 2J"PC# 01[6 HzŁ\ 029[53 s "Cp#\
021[49 t ðCo\ 1J"PC# 8[7 HzŁ\ 039[75 d ðCi\ 0J"PC# 023[4
HzŁ[ 20P NMR "CD2OD\ 010[3 MHz# ] 00[2 s[
1
with weights w−0 ꢂ s1"Fo #¦"9[0992P#1¦1[7920P\
where P ꢂ "Fo −1Fc #:2 ^ goodness!of!_t 0[998[ The
1
1
residual electron density from a _nal di}erence Fourier
synthesis was in the range of 9[412\ −9[642 e_−2
[
RESULTS AND DISCUSSION
The tetraphenylimidodiphosphinic acid and its
sodium salt were prepared using previously described
procedures ð01\02Ł\ and were characterized by IR and
Reaction of ðMn"CO#4ŁBr with Nað"OPPh1#1NŁ
A stoichiometric amount of Nað"OPPh1#1NŁ "0[0 g\ multinuclear NMR spectroscopy[ The resonance sig!
1[44 mmol# was added to a solution of ðMn"CO#4ŁBr nals observed in the 0H and 02C NMR spectra of both
"9[6 g\ 1[44 mmol# in 099 ml anhydrous THF[ The compounds exhibit the expected pattern due to the
reaction mixture was stirred under re~ux until the IR protonÐproton and protonÐphosphorus\ and carbonÐ
spectrum of the crude solution remained unchanged in phosphorus couplings\ respectively[ A signi_cant
0
the region characteristic for CO stretching vibrations[ increase in the J"PC# coupling constant from 090[5
After 9[4 h the formation of a white solid was noted[ Hz in the free acid to 023[4 Hz in the sodium salt was
The NaBr was _ltered o} and the removal of the noted[ In addition\ when the 02C NMR spectrum of
solvent from the clear _ltrate under vacuum resulted Nað"OPPh1#1NŁ was recorded in DMSOd5\ the reson!
in an oily product[ Recrystallization of this material ance for the ipso carbon was further split due to the
from a THF:n!hexane "0 ] 0# solvent mixture resulted coupling to the second phosphorus atom of the ligand
in isolation of Mn"CO#3ð"OPPh1#1NŁ as a white solid[ unit ð0J"PC# ꢂ 018[9 Hz\ 2J"PC# ꢂ 3[2 HzŁ[ However\
Yield ] 9[42 g "25)#\ m[p[ ꢂ 069Ð064>C "dec[#[ IR 20P NMR spectra show only one broad resonance for

A new monomeric manganese "III# complex
1570
both phosphorus atoms\ in the sodium salt the signal Mnð"OPPh1#1NŁ1[ However after a long period of time
being shifted about 09 ppm to lower _eld due to delo! during which the solvent was slowly evaporated a
calization of the electrons over the OPNPO fragment[ purplish!blue solid was _nally obtained[ This was sol!
The
carbonylmanganese"I#
complex\
uble in chloroform and was proved to be the cor!
responding manganese"III# complex[ The compound
was very stable and no decomposition was observed
after several weeks in open atmosphere[
Table 0 contains selected bond distances and angles
in Mnð"OPPh1#1NŁ2 and Fig[ 0 shows the ORTEP!like
view ð04Ł of the molecular structure with the atom
numbering scheme[
The crystal contains discrete molecules of the
manganese"III# complex\ in which the imido!
diphosphinato ligands act as bidentate moieties[ As
expected the PNP fragment\ which in the free acid
has a linear orientation\ becomes now angular ðav[
013[5"5#>Ł to allow the coordination of both oxygen
atoms to the metal[ Although signi_cant di}erences
in the manganeseÐoxygen bond lengths are noted "see
below#\ the corresponding phosphorusÐoxygen dis!
tances are equivalent ðav[ 0[407"8# _Ł as are the phos!
phorusÐnitrogen bonds ðav[ 0[476"6# _Ł[ These values
might be considered of intermediate magnitude
between single and double phosphorusÐoxygen ðcf
Ph1P"1S#OMe ð07Ł ] P0O 0[59"1# _ ^ Ph2P"1O#
ð08Ł ] P1O 0[376"1# _Ł and phosphorus!nitrogen
bonds ðcf Me0S0PPh11N0Ph1P1S ð19Ł ] P0N
0[509"3#\ P1N 0[457"3# _Ł[ However the con!
siderable double bond character of both bond types
is evident[
The six!membered MnO1P1N inorganic rings thus
formed are not planar despite the averaging in bond
lengths due to some delocalization of p!electrons over
the OPNPO fragment[ They exhibit a twisted boat
conformation as re~ected by the torsion angles and
the deviations from the MnO1 planes within a
MnO1P1N ring\ respectively "Table 1#[
For 5!coordinate complexes the octahedral
geometry is the most common[ However in many cases
di}erent degrees of distortion from the octahedron
have been established ð10Ł\ and this is the case for
various manganese"III# complexes with chelating oxo
ligands\ MnL2\ resulting in a MnO5 core "Fig[ 1#[ A
_rst type of distortion is the tetragonal distortion\ that
is either elongation or compression along one of the
fourfold rotational axes of the octahedron\ resulting
in a reduction of symmetry from Oh to D3h[ This is
Mn"CO#3ð"OPPh1#1NŁ\ was prepared by methatesis
according to eq "0# and isolated as a white solid ]
ðMn"CO#4ŁBr¦Nað"OPPh1#1NŁ :
Mn"CO#3 ð"OPPh1#1NŁ¦CO¦NaBr "0#
Its IR spectrum shows a strong absorption assigned
to nas"P1N# stretching vibration at about 0132 cm−0
which is consistent with the coordination of the ligand
in its deprotonated form "cf nas"P1NH# 819 cm−0 in
"OPPh1#1NH\ and nas"P1N# 0159\ 0119 cm−0 in
Nað"OPPh1#1NŁ#[ In the carbonyl stretching region the
expected four bands were observed "1924 vs\ 1997 vs\
0872 vs\ 0813 vs cm−0\ in KBr pellet\ and 1940 vs\ 1901
vs\ 0879 m\ and 0821 m cm−0\ in n!hexane solution#\
corresponding to non!degenerate n"CO# vibrations
"1A0¦B0¦B1# ð05Ł[ This behavior is characteristic of
psuedooctahedral complexes with a carbonyl C1v local
symmetry\ and is consistent with the coordination of
the imidodiphosphinato ligand through both oxygen
atoms[
A monomeric structure "a# might be proposed for
this carbonylmanganese complex in solid state\ similar
to that established for the dithio analog ð0Ł[ However\
a dimeric structure of type "b# cannot be ruled out[
Several attempts to grow X!ray quality crystals of
Mn"CO#3ð"OPPh1#1NŁ
were
performed
using
CHCl2:hexane and CH1Cl1:hexane solutions but
always decomposition of the starting material was
achieved[ The initial colorless solution became violet
within few days and deposited purplish!blue crystals
of the manganese"III# complex Mnð"OPPh1#1NŁ2 "as
proved by X!ray di}ractometry*see below# together
with an amorphous brown solid "probably MnO1#[
The decomposition process might be described by eqn
"1# ]
2 Mn"CO#3 ð"OPPh1#1NŁ¦1 O1 :
Mnð"OPPh1#1NŁ2¦1 MnO1¦01 CO "1#
Attempts to obtain the same manganese"III# com!
pound by oxidizing the manganese"II# complex\
Mnð"OPPh1#1NŁ1 ð06Ł\ with hydrogen peroxide both
in water suspension or chloroform solution have
failed[ No color change was observed when air was the case of the previously reported b! and g!forms
bubbled about out 5 h through a CHCl2 solution of of Mn"acetilacetonato#2 and the distortion has been

1571
N[ Zuniga!Villareal et al[
Table 0[ Selected bond distances "_# and angles "># in Mnð"OPPh1#1NŁ2
Mn"0#0O"0#
Mn"0#0O"1#
Mn"0#0O"2#
Mn"0#0O"3#
Mn"0#0O"4#
Mn"0#0O"5#
1[030"2#
0[842"2#
0[830"2#
0[828"2#
1[007"2#
0[849"2#
cis!O0Mn0O angles
O"0#0Mn"0#0O"1#
O"0#0Mn"0#0O"2#
O"0#0Mn"0#0O"3#
O"0#0Mn"0#0O"5#
O"1#0Mn"0#0O"2#
O"1#0Mn"0#0O"4#
78[8"0#
81[6"0#
77[3"0#
77[8"0#
76[1"0#
78[1"0#
O"1#0Mn"0#0O"5#
O"2#0Mn"0#0O"3#
O"2#0Mn"0#0O"4#
O"3#0Mn"0#0O"4#
O"3#0Mn"0#0O"5#
O"4#0Mn"0#0O"5#
81[9"0#
80[1"0#
76[8"0#
81[3"0#
78[6"0#
89[3"0#
trans!O0Mn0O angles
O"0#0Mn"0#0O"4#
O"1#0Mn"0#0O"3#
O"0#0P"0#0N"0#
O"1#0P"1#0N"0#
067[8"0#
066[5"0#
006[6"1#
006[8"1#
O"2#0Mn"0#0O"5#
067[1"0#
P"0#0O"0#
P"1#0O"1#
P"0#0N"0#
P"1#0N"0#
P"2#0O"2#
P"3#0O"3#
P"2#0N"1#
P"3#0N"1#
P"4#0O"4#
P"5#0O"5#
P"4#0N"2#
P"5#0N"2#
0[402"2#
0[403"2#
0[477"3#
0[484"3#
0[419"2#
0[429"2#
0[473"3#
0[473"3#
0[494"2#
0[413"2#
0[481"3#
0[465"3#
Mn"0#0O"0#0P"0#
Mn"0#0O"1#0P"1#
013[9"1#
020[1"1#
P"0#0N"0#0P"1#
O"2#0P"2#0N"1#
O"3#0P"3#0N"1#
012[8"1#
005[5"1#
005[3"1#
Mn"0#0O"2#0P"2#
Mn"0#0O"3#0P"3#
020[0"1#
029[0"1#
P"2#0N"1#0P"3#
O"4#0P"4#0N"2#
O"5#0P"5#0N"2#
013[8"1#
006[7"1#
006[2"1#
Mn"0#0O"4#0P"4#
Mn"0#0O"5#0P"5#
017[4"1#
018[2"1#
P"4#0N"2#0P"5#
013[8"2#
Fig[ 0[ Three dimensional representation of the molecular structure of Mnð"OPPh1#1NŁ2 "for clarity only ipso carbons
attached to phosphorus atoms are shown#[

A new monomeric manganese "III# complex
1572
Table 1[ Torsion angles "># and least!square planes "deviations\ _# in Mnð"OPPh1#1NŁ2
N"0#P"0#O"0#Mn"0#
O"0#P"0#N"0#P"1#
O"1#P"1#N"0#P"0#
N"0#P"1#O"1#Mn"0#
O"0#Mn"0#O"1#P"1#
O"1#Mn"0#O"0#P"0#
16[4
00[1
−15[5
9[2
14[8
−39[0
N"1#P"2#O"2#Mn"0#
O"2#P"2#N"1#P"3#
O"3#P"3#N"1#P"2#
N"1#P"3#O"3#Mn"0#
O"2#Mn"0#O"3#P"3#
O"3#Mn"0#O"2#P"2#
−01[4
−00[8
7[0
19[6
−22[2
18[0
N"2#P"4#O"4#Mn"0#
O"4#P"4#N"2#P"5#
O"5#P"5#N"2#P"4#
N"2#P"5#O"5#Mn"0#
O"4#Mn"0#O"5#P"5#
O"5#Mn"0#O"4#P"4#
8[5
−11[4
2[0
22[3
−25[6
03[9
Mn"0#O"0#O"1# plane
Mn"0#O"2#O"3# plane
Mn"0#O"4#O"5# plane
P"0#
P"1#
N"0#
−9[798
−9[387
−0[044
P"2#
P"3#
N"1#
9[445
9[532
9[877
P"4#
P"5#
N"2#
9[176
9[696
9[755
Fig[ 1[ MnO5 cores in "a# b!Mnð"OCMe#1CHŁ2\ "b# g!Mnð"OCMe#1CHŁ2\ "c# MnðO1C6H4Ł2 "molecule 1#\ "d# Mnð"OPPh1#1NŁ2
ðfor clarity only carbons attached to oxygen and phosphorus atoms are shown in "c# and "d#\ respectivelyŁ[

Table 2[ Comparative structural data in Mnð"OPPh1#1NŁ2 and related MnO5 core!containing derivativesa
Mnð"OPPh1#1NŁ2
ðthis workŁ
b!Mnð"OCMe#1CHŁ2
g!Mnð"OCMe#1CHŁ2
MnðO1C6H4Ł2 ð13Łb
ð11Ł
ð12Ł
molecule 0
molecule 1
MnO5 core geometryc
tetragonally elongated
MnO5 distortion
0[31
tetragonally compressed
MnO5 distortion
0[30
tetragonally elongated
MnO5 distortion
0[39
tetragonally elongated
MnO5 distortion
0[16
orthorhombic MnO5
distortion
b "_#d
0[16
13[4
0[833"6#
u "degree#e
Mn0O "average#
18[0
0[835"6#
29[0
0[833"07#
18[5
0[824"4#
13[4
0[831"04#
1[029"05#
1[999"05#
1[000"1#
1[016"13#
0[889"3#
1[941"05#
O === O bite "average#
1[74"6#
89[4"9[5#
76[1"9[0#Ð81[6"9[0#
006[5"9[0#Ð067[8"9[0#
018[9"1[6#
1[68"1#
78[5"9[4#
77[7"9[2#Ð80[6"9[2#
067[9"9[3#Ð068[9"9[3#
016[1"9[3#
1[79"3#
78[1"0[4#
76[4"9[0#Ð81[4"9[0#
063[5Ð067[8e
016[0"0[3#
1[45"4#
68[1"0[4#
75[7"9[5#Ð093[0"9[5#
051[8"9[5#Ð062[4"9[5#
004[9"3[0#
1[43"2#
68[9"0[8#
89[9"9[5#Ð86[3"9[5#
058[0"9[5#Ð060[3"9[5#
004[3"1[9#
O0Mn0O "endocyclic\ average#
O0Mn0O "endocyclic\ cis\ range#
O0Mn0O "endocyclic\ trans\ range#
Mn0O0X "average#
0:1
iꢀN
a Esds for average bond length are calculated from the equation s ꢀ
s "xi−x#1:"N−0#
\ where xi is ith bond length and x is the mean of the N equivalent bond lengths[ An analogous
6$
%
iꢀ0
formula is used for the calculation of esds for average bond angles ð14Ł[
b O1C6H4 ꢂ tropolonato[
c TD ꢂ tetrahedral\ SP ꢂ square!planar[
d Normalized bite of the bidentate ligand ð10Ł[
e Twist angle between the upper and lower triangular faces of the MnO5 octahedron ð19Ł[
e Calculated from published atomic coordinates[

A new monomeric manganese "III# complex
1574
Lezama\ M[\ Hernandez!Ortega\ S[ and Alvarez
Toledano\ C[\ J[ Or`anomet[ Chem[\ 0884\ 385\
058[
discussed in connection with the Jahn!Teller e}ect[
The title compound\ Mnð"OPPh1#1NŁ2\ exhibits a simi!
lar tetragonal elongation of the MnO5 octahedral core
"for comparative molecular parameters see Table 2# ]
the axial Mn0O bond distances ðav[ 1[029"05# _Ł are
about 9[07 _ longer than the equatorial Mn0O bond
distances ðav[ 0[835"6# _Ł[ The distortion of the oxy!
gen atom arrangement around the metal is also
re~ected in the magnitude of the O0Mn0O angles[
An elongation or compression along one of the three!
fold rotational axes of the octahedron might also be
expected and results in a trigonal antiprism "D2h#[ The
Mn"tropolonato#2 complex shows an unusual feature\
i[e[ there are two crystallographically independent
molecules ] one is tetragonal elongated\ while the other
one was described as orthorhombical distorted with
three pairs of di}erent Mn0O distances ð13Ł[ It
should be mentioned here that Keppert has considered
an orthorhombical distortion of b!Mnð"OC!
Me#1CHŁ2\ while the two independent molecules in the
unit cell of the Mn"tropolonato#2 complex were both
described as exhibiting di}erent degrees of tetragonal
elongation "3) and 09)# ð10Ł[
1[ Haiduc\ I[\ Sowerby\ D[ B[ and Lu\ S[!F[\ Poly!
hedron\ 0884\ 03\ 2278[
2[ Ebert\ K[ H[\ Breunig\ H[ J[\ Silvestru\ C[\ Stefan\
I[ and Haiduc\ I[\ Inor`[ Chem[\ 0883\ 22\ 0584
and references cited therein[
3[ Silvestru\ C[\ Haiduc\ I[\ Cea!Olivares\ R[ and
Hernandez!Ortega\ S[\ Inor`[ Chim[ Acta\ 0884\
122\ 040[
4[ Silvestru\ C[ and Haiduc\ I[\ Coord[ Chem[ Rev[\
0885\ 036\ 006[
5[ Churchill\ M[ R[\ Crooke\ J[\ Fennessey\ J[ P[ and
Wormald\ J[\ Inor`[ Chem[\ 0860\ 09\ 0920[
6[ Bhattacharyya\ P[\ Novosad\ J[\ Phillips\ J[\
Slawin\ A[ M[ Z[\ Williams\ D[ J[ and Woollins\
J[ D[\ J[ Chem[ Soc[\ Dalton Trans[\ 0884\ 0596[
7[ Rosler\ R[\ Silvestru\ C[\ Espinosa!Perez\ G[\ Hai!
Ã
duc\ I[ and Cea!Olivares\ R[\ Inor`[ Chim[ Acta\
0885\ 130\ 36[
8[ Silvestru\ C[\ RoÃsler\ R[ and Toscano\ R[ A[\
unpublished results[
09[ Greenwood\ N[ N[ and Earnshaw\ A[\ Chemistry
of the Elements[ Pergamon Press\ Oxford\ 0889\
p[ 0117[
Another possibility of distorsion might be con!
sidered for complexes containing MX5 cores the coor!
dination polyhedron being intermediate between a
perfect octahedral symmetry and a trigonal prismatic
coordination[ For M"bidentate ligand#2 complexes
this type of distortion is completely de_ned by the
normalized bite of the bidentate ligand b and the twist
angle u between two opposite triangular faces ð10Ł ]
the shorter the bite distance\ the smaller the twist
angle[ For manganese"III# complexes containing
bidentate dioxo ligands "Table 2#\ if any Jahn!Teller
distortions are ignored and the O0Mn0O bond
angles are averaged assuming a three fold axis\ then
the calculated values of b and u are consistent with
the repulsion!energy calculations ð10Ł[ The ~exibility
of the OPNPO skeleton can allow smaller or larger
O === O bite values as required by the coordination
geometry around the metal atom[ Therefore the tetra!
gonal elongation observed in the case of Mnð"OP!
Ph1#1NŁ2 adds further evidence that the distortion of
the molecular structure of Mn"III# complexes is due
to the Jahn!Teller e}ect[
00[ Quick\ M[ H[ and Angelici\ R[ J[\ Inor`[ Synth[\
0868\ 08\ 059[
01[ Wang\ F[ T[\ Najdzionek\ J[\ Leneker\ K[ L[\
Wasserman\ H[ and Braitsch\ D[ M[\ Synth[
React[ Inor`[ Met[!Or`[ Chem[\ 0867\ 7\ 008[
02[ Day\ R[ O[\ Holmes\ R[ R[\ Schmidpeter\ A[\
Stoll\ K[ and Howe\ L[\ Chem[ Ber[\ 0880\ 013\
1332[
03[ Sheldrick\ G[ M[\ Crystal Structure Re_nement
Ver[ SHELXL!86\ Inst[ Anor`[ Chem[\ Gottingen\
Germany\ 0886[
04[ Sheldrick\ G[ M[\ SHELXL:PC User|s Manual
Siemens Analytical X!Ray\ Inc[\ Madison\ WI\
0889[
05[ Orgel\ L[ E[\ Inor`[ Chem[\ 0851\ 0\ 14[
06[ Szekely\ I[\ Drake\ J[ E[ and Silvestru\ C[\ Phos!
phorus\ Sulfur and Silicon\ 0886\ in press[
07[ Lepicard\ G[\ de Saint!Giniez!Liebig\ D[\ Laur!
ent\ A[ and Rerat\ C[\ Acta Crystallo`r[\ 0858\
B14\ 506[
08[ Baures\ P[ W[ and Silverton\ J[ V[\ Acta Crystal!
lo`r[\ 0889\ C35\ 604[
19[ Silvestru\ C[\ Rosler\ R[ and Espinosa!Perez\ G[\
Ã
unpublished work[
10[ Kepert\ D[ L[\ Pro`r[ Inor`[ Chem[\ 0866\ 12\ 0[
11[ Fackler\ Jr[ J[ P[ and Avdeef\ A[\ Inor`[ Chem[\
0863\ 02\ 0753[
12[ Stults\ B[ R[\ Marianelli\ R[ S[ and Day\ V[ W[\
Inor`[ Chem[\ 0868\ 07\ 0742[
Acknowled`ements*C[S[ acknowledges a visiting fellowship
grant from CONACYT and UNAM[ N[Z[!V[ also acknowl!
edges _nancial support from CONACYT[
13[ Avdeef\ A[\ Costamagna\ J[ A[ and Fackler\ Jr[ J[
P[\ Inor`[ Chem[\ 0868\ 02\ 0743[
14[ Churchill\ M[ R[\ Cooke\ J[\ Wormald\ J[\ Davi!
son\ A[ and Switkes\ E[ S[\ J[ Am[ Chem[ Soc[\
0858\ 80\ 5407[
REFERENCES
0[ Zuniga!Villarreal\ N[\ Silvestru\ C[\ Reyes