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1.
The reaction of K[ReH6(PPh3)2] with [RhCl(CO)L2] [L= PPh3, 1,2,5-triphenylphosphole (TPP), or P(OMe)3] leads to the new electronically unsaturated heterobimetallic polyhydride complexes [(CO)(PPh3)2HRe(μ-H)3RhL2] in moderate-to-good yields. The structures of these complexes have been established on the basis of spectroscopic data, especially 1H and 31P NMR. The bridging hydride ligands are fluxional but there is either a slow or nonexistent exchange between terminal and bridging hydrides. For L = PPh3 or TPP, protonation with tetrafluoroboric acid affords quantitatively the cationic complexes [(CO)(PPh3)2HRe(μ-H)3RhHL2]+, isolated as the BF4− or the BPh4− salts. 相似文献
2.
Alexander Constantin Filippou Ernst Otto Fischer 《Journal of organometallic chemistry》1986,310(3):357-366
The reaction of trans-X(CO)4WCNR2 (X = Br, R = c hex (cyclohexyl); X = Cl, R = c hex, ipr (isopropyl) with M+X− (M+ = NEt4+, X− = Br−; M+ = PPN+, X− = Cl−) leads under substitution of one CO ligand to new anionic dihalo(tricarbonyl)carbyne-tungsten complexes of the type M+ mer-[(X)2(CO)3WCNR2]− (M+ = NEt4+, X = Br, R = c hex; M+ = PPN+, X = Cl, R = c hex, i pr), whose composition and structure were determined by elemental analysis as well as by IR, 1H and 13C NMR spectroscopy. In the anionic carbyne complexes the entered halogen ligand, coordinated in a cis position relative to the carbyne ligand on the metal, can be easily substituted by neutral nucleophiles, as the reaction of PPN+ mer-[(Cl)2(CO)3WCNchex2]− with PPh3 demonstrates yielding the neutral carbyne complex mer-[Cl(CO)3(PPh3)WCNchex2]. 相似文献
3.
The reaction of [(CO)PPh3)2Re(μ-H)2(μ-NCHPh)Ru(PPh3)2(PhCN)] (2) with HBF4-Me2O generates [(CO)PPh3)2Re(μ- H)2(μ,η1,η2HNCHPh)Ru(PPh3)2(PhCN)][BF4] (3). Monitoring the reaction by NMR spectroscopy shows the intermediate formation of [(CO)(PPh3)2 HRe(μ-H)2(μ-NCHPh)Ru(PPh3)2(PhCN)][BF4] (4). Attempted reduction of the imine ligand by a nucleophile (H− or CN−) failed, regenerating 2. Under dihydrogen at 50 atm, 3 is slowly transformed into [(CO)(PPh3)2HRe(μ-H)3Ru(PPh3)2(PhCN)][BF4] (5) with liberation of benzyl amine. 相似文献
4.
Kom-Bei Shiu Shin-Jay Yu Yu Wang Gene-Hsiang Lee 《Journal of organometallic chemistry》2002,650(1-2):37-42
Treatment of [Ru2(CO)4(MeCN)6][BF4]2 or [Ru2(CO)4(μ-O2CMe)2(MeCN)2] with uni-negative 1,1-dithiolate anions via potassium dimethyldithiocarbamate, sodium diethyldithiocarbamate, potassium tert-butylthioxanthate, and ammonium O,O′-diethylthiophosphate gives both monomeric and dimeric products of cis-[Ru(CO)2(η2-(SS))2] ((SS)−=Me2NCS2− (1), Et2NCS2− (2), tBuSCS2− (3), (EtO)2PS2− (4)) and [Ru(CO)(η2-(Me2NCS2))(μ,η2-Me2NCS2)]2 (5). The lightly stabilized MeCN ligands of [Ru2(CO)4(MeCN)6][BF4]2 are replaced more readily than the bound acetate ligands of [Ru2(CO)4(μ-O2CMe)2(MeCN)2] by thiolates to produce cis-[Ru(CO)2(η2-(SS))2] with less selectivity. Structures 1 and 5 were determined by X-ray crystallography. Although the two chelating dithiolates are cis to each other in 1, the dithiolates are trans to each other in each of the {Ru(CO)(η2-Me2NCS2)2} fragment of 5. The dimeric product 5 can be prepared alternatively from the decarbonylation reaction of 1 with a suitable amount of Me3NO in MeCN. However, the dimer [Ru(CO)(η2-Et2NCS2)(μ,η2-Et2NCS2)]2 (6), prepared from the reaction of 2 with Me3NO, has a structure different from 5. The spectral data of 6 probably indicate that the two chelating dithiolates are cis to each other in one {Ru(CO)(η2-Et2NCS2)2}fragment but trans in the other. Both 5 and 6 react readily at ambient temperature with benzyl isocyanide to yield cis-[Ru(CO)(CNCH2Ph)(η2-(SS))2] ((SS)=Me2NCS2− (7) and Et2NCS2− (8)). A dimerization pathway for cis-[Ru(CO)2(η2-(SS))2] via decabonylation and isomerization is proposed. 相似文献
5.
The preparations and spectroscopic characteristics are reported of a series of (trimethylgermyl)methyl- and (trimethylstannyl)methylplatinum(II) complexes with diene and P-donor ancillary ligands, cis-Pt(CH2GeMe3)2L2 (L = PPh3 or PPh2Me; L2 = dppe or cod) and cis-Pt(CH2SnMe3)2L2 (L = PPh3; L2 =cod). Thermolysis of toluene solutions of cis-Pt(CH2GeMe3)2(PPh3)2 leads to cis-Pt(Me)(CH2GeMe2CH2GeMe3)(PPh3)2 via β-alkyl migration, after (non-rate-limiting) phosphine dissociation. Estimated activation parameters (ΔH298 K‡ = 126 ± 3 kJ mol−1, ΔS‡ = + 17 ± 7 J mol−1 K−1 and hence Δ298 K‡ = 121 ± 5 kJ mol−1) suggest that this system is more migration labile than its silicon analogue, primarily as a result of a lower activation enthalpy. While cis-Pt(CH2GeMe3)2(PPh2Me)2 reacts similarly but less readily, Pt(CH2GeMe3)2(dppe)2 is inert at operable temperatures. Thermolysis of Pt(CH2GeMe3)2(cod) generates 1,1,3,3,-tetramethyldi-1,3-germacyclobutane as the major organogermanium product, while from cis-Pt(CH2SnMe3)2(PPh3)2, 1,1,3,3-tetramethyldi-1,3-stannacyclobutane predominates. Mechanistic implications are discussed. 相似文献
6.
M. F tima C. Guedes da Silva Elsa M. P. R. P. Branco Yu Wang Jo o J. R. Fraú sto da Silva Armando J. L. Pombeiro Roberta Bertani Rino A. Michelin Mirto Mozzon Franco Benetollo Gabriella Bombieri 《Journal of organometallic chemistry》1995,490(1-2):89-99
Complexes trans-[PtX(L)(PPh3)2]A [1: X = CF3; A = BF4; L = NCNH2, NCNMe2, NCNEt2, or NCNC(NH2)2. 2: X = Cl; A = BPh4; L = NCNMe2 or NCNEt2] and cis-[PtCl(L)(PPh3)2][BPh4] [3: L = NCNH2 or NCNC(NH2)2], which appear to be the first cyanamide or cyanoguanidine complexes of platinum to be reported, have been prepared by treatment of trans-[PtBr(CF3)(PPh3)2] (in CH2Cl2/acetone and in the presence of Ag[BF4]) or of cis-[PtCl2(PPh3)2] (in THF and in the presence of Na[BPh4]), respectively, with the appropriate substrate. In KBr pellets or in solution 1 (L = NCNMe2 or NCNEt2) undergoes ready replacement of the organocyanamide (under the trans influence of CF3) by bromide to regenerate trans-(PtBr(CF3)(PPh3)2]. The X-ray structure of 1 (X = CF3, A = BF4, L = NCNEt2) is also reported, and shows the presence of two apical intramolecular contacts of the metal with two ortho-hydrogen atoms of the phosphines, whereas the amine N atom of the diethylcyanamide is trigonal planar in the linear NCN framework with a delocalized π system. 相似文献
7.
The molecular and crystal structure of the nido-6-tungstadecaborane [6,6,6,6-(CO)2(PPh3)2-nido-6-WB9H13] (1) has been determined showing that the tungsten atom is incorporated into the 6-position of a nido 10-vertex (WB9) cage. The tungsten atom has a seven-coordinate capped trigonal prismatic environment and is bonded to two hydrogen and three boron atoms of the {B9H13} cage, in addition to two CO groups and two PPh3 ligands. Variable-temperature (−90°C to +50°C) 31P{1H} NMR spectroscopy of 1 reveals that the exo-polyhedral ligands about the tungsten atom are fluxional with respect to PPh3 site exchange with an activation energy (ΔG‡), at the coalescence temperature (−73°C), of <38 kJ mol−1. 相似文献
8.
Günter Urban Karlheinz Sünkel Wolfgang Beck 《Journal of organometallic chemistry》1985,290(3):329-339
The compounds (π-C5H5)(CO)2LM-X (L = CO, PR3; M = Mo, W; X = BF4, PF6, AsF6, SbF6) react with H2S, p-MeC6H4SH, Ph2S and Ph2SO(L′) to give ionic complexes [(π-C5H5)(CO)2LML′]+ X−. Also sulfur-bridged complexes, [(π-C5H5)(CO)3W---SH---W(CO)3(π-C5H5)]+ AsF6− and [(π-C5H5)(CO)3M-μ-S2C=NCH2Ph-M(CO)3(π-C5H5)], have been obtained. Reactions with SO2 and CS2 have been examined. 相似文献
9.
Isabel Moldes Sergeï Nefedov Noël Lugan Ren Mathieu 《Journal of organometallic chemistry》1995,490(1-2):11-19
The reaction of K[H6ReL2] with [RuHCl(CO)(PPh3)3−x {P(OPri}3)x](L2 = (PMePh2)2, dppe, (AsPh3)2, or (PPh3)2; x = 0, 1 or 2) leads to [L2(CO)HRe(μ-H)3RuH(PPh3)2−y{P(OPri)3}y] (x = 0 or 1, Y = 0; X = 2, Y = 1(L2 = PPh3)) in a first step. Under the reaction conditions most of these complexes react rapidly with the liberated phosphine giving [L2(CO)Re(μ-H)3Ru(PPh3)3−y- {P(OPri)3}y] (L2 = (PMePh2)2 or dppe, Y = 0; L2 = (PPh3)2, Y = 1) as the only iso complexes. The structure of [(PMePh2)2(CO)Re(μ-H)3Ru(PPh3)3] has been establishedby X-ray structure analysis. The complex [(PPh3)2(CO)Re(μ-H)3Ru(PPh3)2(P(OPri)3)] reacts with molecular hydrogen under pressure to generate [L2(CO)HRe(μ-H)3RuH(PPh3)(P(OPri)3) as the sole product. 相似文献
10.
Javier A. Cabeza Angela Llamazares Víctor RieraPierrette Briard Lahcne Ouahab 《Journal of organometallic chemistry》1994,480(1-2):205-212
The compound [RU3(μ3,η2- -ampy)(μ3η1:η2-PhC=CHPh)(CO)6(PPh3)2] (1) (ampy = 2-amino-6-methylpyridinate) has been prepared by reaction of [RU3(η-H)(μ3,η2- ampy) (μ,η1:η2-PhC=CHPh)(CO)7(PPh3)] with triphenylphosphine at room temperature. However, the reaction of [RU3(μ-H)(μ3, η2 -ampy)(CO)7(PPh3)2] with diphenylacetylene requires a higher temperature (110°C) and does not give complex 1 but the phenyl derivative [RU3(μ3,η2-ampy)(μ,η 1:η2 -PhC=CHPh)(μ,-PPh2)(Ph)(CO)5(PPh3)] (2). The thermolysis of complex 1 (110°C) also gives complex 2 quantitatively. Both 1 and 2 have been characterized by0 X-ray diffraction methods. Complex 1 is a catalyst precursor for the homogeneous hydrogenation of diphenylacetylene to a mixture of cis- and trans -stilbene under mild conditions (80°C, 1 atm. of H2), although progressive deactivation of the catalytic species is observed. The dihydride [RU3(μ-H)2(μ 3,η2-ampy)(μ,η1:η2- PhC=CHPh)(CO)5(PPh3)2] (3), which has been characterized spectroscopically, is an intermediate in the catalytic hydrogenation reaction. 相似文献
11.
Yu Wang Jo oJr. Fraú sto Da Silva Armando J. L. Pombeiro
Maria Angela Pellinghelli
Ant nio Tiripicchio 《Journal of organometallic chemistry》1992,430(3):C56-C59The nitrosyl complexes trans-[ReCl(NO)(dppe)2]A2 (1; A = BF4 or NO3; dppe = Ph2PCH2CH2−PPh2) and trans-[ReCl(NO)(dppe)2][BF4] (2) have been prepared from the reactions of NO[BF4] or NO with trans-[ReCl(N2)dppe)2]. An unusual facile oxidation of NO to nitrate is involved in the formation of (1, A = NO3), the X-ray structure of which is reported. 相似文献
12.
Darryl P. Klein N. Quir s M ndez Jeffery W. Seyler Atta M. Arif J. A. Gladysz 《Journal of organometallic chemistry》1993,450(1-2):157-164
The crystal structures of propionaldehyde complex (RS,SR)-(η5-C5H5)Re(NO)(PPh3)(η2-O=CHCH2CH3)]+ PF6− (1b+ PF6s−; monoclinic, P21/c (No. 14), a = 10.166 (1) Å, b = 18.316(1) Å, c = 14.872(2) Å, β = 100.51(1)°, Z = 4) and butyraldehyde complex (RS,SR)-[(η5-C5H5)Re(NO)(PPh3)(η2-O=CHCH2CH2CH3)]+ PF6− (1c+PF6−; monoclinic, P21/a (No. 14), a = 14.851(1) Å, b = 18.623(3) Å, c = 10.026(2) Å, β = 102.95(1)°, Z = 4) have been determined at 22°C and −125°C, respectively. These exhibit C
O bond lengths (1.35(1), 1.338(5) Å) that are intermediate between those of propionaldehyde (1.209(4) Å) and 1-propanol (1.41 Å). Other geometric features are analyzed. Reaction of [(η5-C5H5)Re(NO)(PPh3)(ClCH2Cl)]+ BF4− and pivalaldehyde gives [(η5-C5H5)Re(NO)(PPh3)(η2-O=CHC(CH3)3)]+BF4− (81%), the spectroscopic properties of which establish a π C
O binding mode. 相似文献
13.
James C. Fettinger Melvyn Rowen Churchill Karen A. Bernard Jim D. Atwood 《Journal of organometallic chemistry》1988,340(3):377-388
The adducts of O2 and SO2 with trans-MeOIr(CO)(PPh3)2 are formed in equilibria and have been characterized. Reaction of the SO2 adduct, Ir(OMe)(SO2)(CO)(PPh3)2 with dioxygen leads to the sulfato complex, Ir(Ome)(CO)(PPh3)2(SO4), the structure of which has been determined. Ir(Ome)(CO)(PPh3)2(SO4) crystallizes in the monoclinic system with a 11.958(2), b 14.163(3), c 12.231(2) Å, β 118.365(12)°, V 1822.7(6) Å3 and Z = 2. Diffraction data for 2θ = 4.5–45.0° (Mo-K) were collected with a Syntex P21 diffractometer and the structure was solved (assuming space group P21/m and an unpleasant 2-fold disordered model) and refined to R = 4.8% for all 2512 independent data (R = 3.5% for those 2042 data with ¦FO¦ > 6σ(¦F¦)). The iridium(III) atom has a distorted octahedral coordination sphere with trans PPh3 ligands and a cis-chelating bidentate O,O′-SO4 group; the structure is completed by mutually cis OMe and CO ligands. 相似文献
14.
Oleg V. Gusev Tat'yana A. Peganova Mikhail G. Peterleitner Svetlana M. Peregudova Larisa I. Denisovich Nikolai A. Ustynyuk
Peter M. Maitlis
《Journal of organometallic chemistry》1994,480(1-2):c16-c17Reaction of [Pt2(η5-C5Me5)2(η-Br)3]3+(Br−)3 with C5R5H (R = H,Me) in the presence of AgBF4 gives the first platinocenium dications, [Pt(η5-C5Me5)(η5-C5R5)]2+(BF4− )2. On electrochemical reduction, [pt(η5-C5Me5)2]2+ yields [Pt(η4-C5Me5H)(η2-C5Me5)]+ BF4−. kw]Cyclopentadienyl; Metallocenes; Platinum; Electrochemistry 相似文献
15.
F. Trautner E. H. Cutin C. O. Della Vedova H. Oberhammer 《Journal of Molecular Structure》1999,510(1-3):53-58
The molecular structure and conformational properties of O=C(N=S(O)F2)2 (carbonylbisimidosulfuryl fluoride) were determined by gas electron diffraction (GED) and quantumchemical calculations (HF/3-21G* and B3LYP/6-31G*). The analysis of the GED intensities resulted in a mixture of 76(12)% syn–syn and 24(12)% syn–anti conformer (ΔH0=H0(syn–anti)−H0(syn–syn)=1.11(32) kcal mol−1) which is in agreement with the interpretation of the IR spectra (68(5)% syn–syn and 32(5)% syn–anti, ΔH0=0.87(11) kcal mol−1). syn and anti describe the orientation of the S=N bonds relative to the C=O bond. In both conformers the S=O bonds of the two N=S(O)F2 groups are trans to the C–N bonds. According to the theoretical calculations, structures with cis orientation of an S=O bond with respect to a C–N bond do not correspond to minima on the energy hyperface. The HF/3-21G* approximation predicts preference of the syn–anti structure (ΔE=−0.11 kcal mol−1) and the B3LYP/6-31G* method results in an energy difference (ΔE=1.85 kcal mol−1) which is slightly larger than the experimental values. The following geometric parameters for the O=C(N=S)2 skeleton were derived (ra values with 3σ uncertainties): C=O 1.193 (9) Å, C–N 1.365 (9) Å, S=N 1.466 (5) Å, O=C–N 125.1 (6)° and C–N=S 125.3 (10)°. The geometric parameters are reproduced satisfactorily by the HF/3-21G* approximation, except for the C–N=S angle which is too large by ca. 6°. The B3LYP method predicts all bonds to be too long by 0.02–0.05 Å and the C–N=S angle to be too small by ca. 4°. 相似文献
16.
The oxidation of Cp2MCl2 (M= Mo, W) with perfluortriazinium tetrafluoroborate, [(FCN)3F]+[BF4]−, in the presence of a flouride ion acceptor (BF3 or PF5) in SO2 solution yielded the cationic metallocene complexes [Cp2MCl 2]2+[BF4]− or [Cp2MCl2] 2+[BF4]−[PF6]− (M = Mo, W), respectively. In these reactions, for the first time the perfluortriazinium cation has proved to be easy to handle and a useful oxidizer in organometallic chemistry. The oxidizer strength of three fluorotriazinium cations, [(XCN)3F]+ (X = F, Cl, H), has been computed ab initio (HF/6 − 31 + G) and calibrated on literature data which were obtained by local density functional calculations. It was anchored to its F+ zero point by an experimental value for KrF+. ab]Die Oxidation von Cp2MCl2 mit (M = MO, W) Perfluortriaziniumtetrafluoroborat, [(FCN)3F]+[BF4]−, in Anwesenheit eines Fluoridionenakzeptors (BF3 oder PF5) führte in SO2-Lösung zur Bildung der kationischen Metallocen-Komplexe [Cp2MCl2+]2+[BF4]2− bzw. [Cp2MCl2]2+[BF4]− [PF6]− (M = Mo, W). In diesen Reaktionen konnte erstmals gezeigt werden, daß Perfluortriazinium-Kationen einfach zu handhabende und nützliche Oxidationsmittel im Bereich der metallorganischen Synthese darstellen. Das (Mdationsvermögen von drei Fluorotriazinium-Kationen, [(XCN)3F]+(X = F, Cl, H), wurde ab initio berechnet (HF/6 − 31 + G) und mit Hilfe von Literaturdaten, die mittels local density functional-Berechnungen erhalten und am experimentellen Wert von KrF + bezüglich des F+ Nullpunktes verankert wurden, kalibriert. 相似文献
17.
The kinetic parameters were determined for C-trifluoromethylation of aniline with S-(trifluoromethyl)dibenzothiophenium triflate (1), its 3,7-dinitro derivative (2) and S-(trifluoromethyl)diphenylsulfonium triflate (3) in DMF-d7. The higher reactivity of heterocyclic 1 compared with non-heterocyclic 3 could be explained on the basis of its greatly enhanced activation entropy (ΔS≠: −11.2 cal mol −1 K−1 for 1; −47.1 for 3), but not its enhanced activation enthalpy (ΔH≠: 21.2 kcal mol−1 for 1; 12.1 for 3). The aromatic delocalization of the heterocyclic ring may thus be only slightly disturbed by the S-trifluoromethyl substituent. The high reactivity of 2 was attributed to the great electron deficiency caused by two nitro groups in addition to the heterocyclic salt system (ΔH≠ 17.0 kcal mol−1, ΔS≠ −9.1 cal mol−1 K−1 for 2). The reaction mechanism is discussed; the conventional SN2 attack mechanism was ruled out and a mechanism for a side-on attack to the CF3-S bond may possibly be applicable. 相似文献
18.
Alison J. Downard Brian H. Robinson Jim Simpson 《Journal of organometallic chemistry》1987,320(3):363-384
The generality of a two-electron reduction process involving an
mechanism has been established for M3(CO)12 and M3(CO)12−n(PPh3)n (M = Ru, Os) clusters in all solvents. Detailed coulometric and spectral studies in CH2Cl2 provide strong evidence for the formation of an ‘opened’ M3(CO)122− species the triangulo radical anions M3(CO)12−· having a half-life of < 10−6 s in CH2Cl2. However, the electrochemical response is sensitive to the presence of water and is concentration dependent. An electrochemical response for “opened” M3(CO)122− is only detected at low concentrations < 5 × 10−4 mol dm−3 and under drybox conditions. The electroactive species ground at higher concentrations and in the presence of water M3(CO)112− and M6(CO)182− were confirmed by a study of the electrochemistry of these anions in CH2Cl2; HM3(CO)11− is not a product. The couple [M6(CO)18]−/2− is chemically reversible under certain conditions but oxidation of HM3(CO)11− is chemically irreversible. Different electrochemical behaviour for Ru3(CO)12 is found when [PPN][X] (X = OAc−, Cl−) salts are supporting electrolytes. In these solutions formation of the ultimate electroactive species [μ-C(O)XRu3(CO)10]− at the electrode is stopped under CO or at low temperatures but Ru3(CO)12−· is still trapped by reversible attack by X presumably as [η1-C(O)XRu3(CO)11]−. It is shown that electrode-initiated electron catalysed substitution of M3(CO)12 only takes place on the electrochemical timescale when M = Ru, but it is slow, inefficient and non-selective, whereas BPK-initiated nucleophilic substitution of Ru3(CO)12 is only specific and fast in ether solvents particulary THF. Metal---metal bond cleavage is the most important influence on the rate and specificity of catalytic substitution by electron or [PPN]-initiation. The redox chemistry of M3(CO)12 clusters (M = Fe, Ru, Os) is a consequence of the relative rates of metal---metal bond dissociation, metal-metal bond strength and ligand dissociation and in many aspects resembles their photochemistry. 相似文献
19.
Helmut Fischer David Reindl Carsten Troll 《Journal of organometallic chemistry》1994,480(1-2):221-225
The successive reaction of chromium and tungsten hexacarbonyl, (CO)6M (M = Cr, W), with [N=C(Ph)R]− and [Et3O]BF4 yields the alkylideneamino(ethoxy)carbene complexes (CO)5M[C(OEt)N=C(Ph)R] (M = Cr (1), W (2); R = NMe2 (a), tBu (b)). Ethoxide abstraction from 1 and 2 affords 2-azoniaallenylidene complexes, {(CO)5M[CNC(Ph)R]}+BF4− (3/4). The complexes 3 and 4 are best described as resonance hybrids of several limiting structures. On the basis of the spectroscopic data of the complexes 3a and 4a the limiting structure of an iminium-substituted isocyanide complex dominates. 相似文献
20.
Beiping Liu Zhi-Cheng Tan Dashun Zhang Zhaodong Nan Lixian Sun Fen Xu Xiaozhen Lan Ping Liang Xiaomei Yu 《Thermochimica Acta》2002,390(1-2):31-37
[Re2(Ala)4(H2O)8](ClO4)6 (Re=Eu, Er; Ala=alanine) were synthesized, and the low-temperature heat capacities of the two complexes were measured with a high-precision adiabatic calorimeter over the temperature range from 80 to 370 K. For [Eu2(Ala)4(H2O)8](ClO4)6, two solid–solid phase transitions were found, one in the temperature range from 234.403 to 249.960 K, with peak temperature 243.050 K, the other in the range from 249.960 to 278.881 K, with peak temperature 270.155 K. For [Er2(Ala)4(H2O)8](ClO4)6, one solid–solid phase transition was observed in the range from 270.696 to 282.156 K, with peak temperature 278.970 K. The molar enthalpy increments, ΔHm, and entropy increments,ΔSm, of these phase transitions, were determined to be 455.6 J mol−1, 1.87 J K−1 mol−1 at 243.050 K; 2277 J mol−1, 8.43 J K−1 mol−1 at 270.155 K for [Eu2(Ala)4(H2O)8](ClO4)6; and 4442 J mol−1, 15.92 J K−1 mol−1 at 278.970 K for [Er2(Ala)4(H2O)8](ClO4)6. Thermal decompositions of the two complexes were investigated by use of the thermogravimetric (TG) analysis. A possible mechanism for the thermal decomposition is suggested. 相似文献