Bis­(di‐μ‐acetato‐aqua{2‐[N‐ethyl‐N‐(2‐hydroxy‐4‐methyl­benzyl)­amino­methyl]‐1‐methyl­benz­imid­az­ole}­nickel)­nickel(II) tetra­hy­drate

The previously unknown title compound, tetra‐μ‐ace­tato‐1:2κ²O;1:2κ²O:O′;­2:3κ²O;­2:3κ²O:O′‐di­aqua‐1κO,3κO‐bis­(μ‐2‐{[N‐ethyl‐N‐(2‐hy­droxy‐5‐methylbenzyl)­am­ino]­methyl}‐1‐methyl‐1H‐benz­imid­az­ole)‐1κ³N³,N,O:2κO;3κ³N³,N,O:2κO‐tri­nickel(II) tetra­hy­drate, [Ni₃(C₁₈H₂₂N₃O)₂(C₂H₃O₂)₄(H₂O)₂]·­4H₂O, (I), is a centrosymmetric linear trinuclear nickel(II) complex, where the Ni atoms are in an octahedral coordination and the ligand heteroatoms act so as to model amino acid residues.     

catena‐Poly­[europium‐tri‐μ‐4‐methyl­benzoato]

Each Eu³⁺ ion in the title compound, catena‐poly­[europium(III)‐tri‐μ‐4‐methyl­benzoato‐O:O,O′;O:O,O′;O,O′:O′], {[Eu(C₈H₇O₂)₃]₃}_n, is coordinated by nine O atoms, and three Eu atoms form a trimeric unit. These trimeric units are linked by bridging–chelating carboxyl­ates to form an infinite one‐dimensional polymer chain.     

Two mixed‐metal carboxyl­ate–base adducts

The crystal structures of hexa‐μ‐propionato‐1:2κ⁶O:O′;1:3κ⁶O:O′‐di­quinoline‐2κN,3κN‐calcium(II)­dizinc(II), [Ca­Zn₂(C₃H₅O₂)₆(C₉H₇N)₂], and hexa‐μ‐pivalato‐1:2κ⁶O:O′;1:3κ⁶O:O′‐di­quinoline‐2κN,3κN‐calcium(II)­dicobalt(II), [Ca­Co₂(C₅H₉O₂)₆(C₉H₇N)₂], are described. Both contain a linear array of one Ca^II ion and two M^II (M = Zn, Co) ions connected by two sets of three carboxyl­ate ligands in syn–syn bridging modes. The distorted tetrahedral geometry around the M^II ion is completed by a quinoline N atom. The central Ca^II ion occupies a crystallographic inversion centre and is octahedrally coordinated by six carboxyl O atoms in each structure. The Zn^II?Ca^II and Co^II?Ca^II distances are 3.8504 (9) and 3.7929 (5) Å, respectively.     

Poly­[disilver(I)‐μ8‐1,5‐naphthalene­disulfonato]

The title complex, poly­[disilver(I)‐μ₈‐1,5‐naphthalene­di­sulfon­ato‐3,4‐η:7,8‐η:κ⁶O:O′:O′′:O′′′:O′′′′:O′′′′′], [Ag₂(C₁₀H₆O₆S₂)]_n, exists as a three‐dimensional framework of Ag^I atoms connected by η¹⁰,μ₈‐1,5‐naphthalene­di­sulfonate ligands through both Ag–sulfonate and Ag–η²‐arene interactions. Each Ag^I atom exhibits a distorted tetrahedral geometry defined by three O atoms of independent sulfonate groups and one C=C bond of the naphthalene group.     

Di‐μ‐sulfito‐bis­[(4,4′‐di­methyl‐2,2′‐bi­pyridine)­zinc(II)] dihydrate and poly­[[aqua(1,10‐phenanthroline)­zinc(II)]‐μ3‐sulfito‐zinc(II)‐μ3‐sulfito]

Two different zinc sulfite compounds have been prepared through the decomposition of pyrosulfite–­di­thionite ions in aqueous solution, viz. a dimeric complex, di‐μ‐sulfito‐κ³O,O′:O′′;κ³O:O′,O′′‐bis­[(4,4′‐di­methyl‐2,2′‐bi­pyridine‐κ²N,N′)­zinc(II)] dihydrate, [Zn₂(SO₃)₂(C₁₂H₁₂N₂)₂]·2H₂O, (I), which was solved and refined from a twinned sample, and an extended polymer, poly­[[aqua(1,10‐phenanthroline‐κ²N,N′)­zinc(II)]‐μ₃‐sulfito‐κ²O:O′:O′′‐zinc(II)‐μ₃‐sulfito‐κ³O:O:O′], [Zn₂(SO₃)₂(C₁₂H₁₀N₂)(H₂O)]_n, (II). In (I), the dinuclear Zn^II complex has a center of symmetry. The cation is five‐coordinate in a square‐pyramidal arrangement, the anion fulfilling a bridging chelating role. Compound (II) comprises two different zinc units, one being five‐coordinate (square pyramidal) and the other four‐coordinate (trigonal pyramidal), and two independent sulfite groups with different binding modes to the cationic centers.     

Tetra‐μ‐2‐fluoro­benzoato‐bis[aqua(4,4′‐bi­pyridine)(2‐fluorobenzoato)lanthanum(III)]

Each La³⁺ ion in the title complex, tetra‐μ‐2‐fluorobenzoato‐κ¹⁰O:O′;O:O,O′;O:O′;O,O′:O′‐bis[aqua(4,4′‐bipy­ridine‐κN)(2‐fluorobenzoato‐κO)lanthanum(II)], [La(C₇H₄FO₂)₆(C₁₀H₈N₂)₂(H₂O)₂], is coordinated by six O atoms from the carboxyl­ate groups of five 2‐fluoro­benzoate ligands, one O atom from a water mol­ecule and one N atom from a 4,4′‐bi­pyridine mol­ecule, thus forming a dimeric mol­ecule. An infinite one‐dimensional dimeric supramolecular chain is formed via intermolecular hydrogen bonds.     

<Emphasis Type="Italic">O</Emphasis>- and <Emphasis Type="Italic">N</Emphasis>-Alkylation of <Emphasis Type="Italic">N</Emphasis>-halosuccinimides in ionic reactions with 1-phenyltricyclo [4.1.0.0<Superscript>2,7</Superscript>]heptane

N-Bromo and N-chlorosuccinimides add to 1-phenyltricyclo[4.1.0.0^2,7]heptane in CH₂Cl₂ with cleavage of the C(1)-C(7) bond to give isomeric 1 : 1 Markownikoff-type endo, anti-adducts of the norpinane structure in a ∼3 :7 ratio corresponding to N and O alkylation of succinimide.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No.2, pp. 457–460, February, 2005     

Bis(2,2‐bi­pyridine‐N,N′)tetra‐μ‐chloro‐tetracopper(I)

A novel centrosymmetric chair‐like dimer, bis(2,2′‐bi­pyridine)‐1κ²N,N′;3κ²N,N′‐tetra‐μ‐chloro‐1:2κ²Cl;­2:3κ²Cl;­3:4κ²Cl;1:4κ²Cl‐tetra­copper(I), [Cu₄Cl₄­(C₁₀­H₈­N₂)₂], has been solvothermally synthesized and structurally characterized. The complex self‐assembles into a three‐dimensional network via C—H?Cl hydrogen bonds, π–π stacking and weak Cu?Cl electrostatic interactions.     

A theoretical study on the stability difference of the borane and carborane C2Bn−2Hn (5 ≤ n ≤ 7) clusters

In order to study the electronic structure and structural stability of borane and carborane C₂B_n?2H_n (5 ≤ n ≤ 7) clusters, especially the stability difference between the borane and carborane C₂B₃H₅. The frontier orbital energy levels of the borane and carborane C₂B_n?2H_n (5 ≤ n ≤ 7) clusters are calculated at CCSD(T)/aug‐cc‐pVXZ//B3LYP/def2‐TZVPP level. The results are further analyzed by qualitative frontier orbital method based on the cap–ring interaction. The results reveal that: (1) the larger E_gap(HOMO‐LUMO energy gap) of carborane C₂B_n?2H_n (5 ≤ n ≤ 7) clusters than borane (5 ≤ n ≤ 7) clusters originates from the more effective cap–ring orbital overlap of carborane C₂B_n?2H_n (5 ≤ n ≤ 7) clusters than that of borane (5 ≤ n ≤ 7) clusters; (2) the smallest E_gap of the borane results from the highest energy level of the ring symmetry‐adapted linear combination orbital of cluster; and (3) the largest E_gap of the carborane C₂B₃H₅ is induced by the most effective cap–ring orbital interaction of C₂B₃H₅ cluster. © 2014 Wiley Periodicals, Inc.     

Synthesis and self‐assembly of amphiphilic brush‐dendritic‐linear poly[poly(ethylene glycol) methyl ether methacrylate]‐b‐ polyamidoamine‐b‐poly(ε‐caprolactone) copolymers

A series of novel amphiphilic brush‐dendritic‐linear poly[poly(ethylene glycol) methyl ether methacrylate]‐b‐polyamidoamine‐b‐poly(ε‐caprolactone) copolymers (PPEGMEMA‐b‐D_m‐b‐PCL) (m = 1, 2, and 3: the generation number of dendron) were synthesized by the combination techniques of click chemistry, atom transfer radical polymerization (ATRP), and ring‐opening polymerization (ROP). The brush‐dendritic copolymers bearing hydrophilic brush PPEGMEMA and hydrophobic dendron polyamidoamine protected by the tert‐butoxycarbonyl (Boc) groups [D_m‐(Boc) (m = 1, 2, and 3)] were for the first time prepared by ATRP of poly(ethylene glycol) methyl ether methacrylate monomer (PEGMEMA) initiated with the dendron initiator, which was prepared from 2′‐azidoethyl‐2‐bromoisobutyrate (AEBIB) and D_m‐(Boc) terminated with a clickable alkyne by click chemistry. Then, the brush‐dendritic copolymers with primary amine groups (PPEGMEMA‐b‐D_m) were obtained from the removal of the protected Boc groups of the brush‐dendritic copolymers in the presence of trifluoroacetic acid. The brush‐dendritic‐linear PPEGMEMA‐b‐D_m‐b‐PCL copolymers were synthesized from ROP of ε‐caprolactone monomer using PPEGMEMA‐b‐D_m as the macroinitiators and stannous octoate as catalyst in toluene at 130 °C. To the best of our knowledge, this is the first report that integrates hydrophilic brush polymer PPEGMEMA with hydrophobic polyamidoamine (PAMAM) dendron and PCL to form amphiphilic brush‐dendritic‐linear copolymers. The amphiphilic brush‐dendritic‐linear copolymers can self‐assemble into spherical micellar structures in aqueous solution. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

catena‐Poly[[bis[aqua­(1,10‐phenanthroline)lead(II)]‐di‐μ3‐5‐carboxy‐3‐sulfonatobenzoato] dihydrate]

In the centrosymmetric title polymer, catena‐poly[[bis[aqua­(1,10‐phenanthroline‐κ²N,N′)lead(II)]‐di‐μ₃‐5‐carboxy‐3‐sulfonatobenzoato‐1:2:1′κ⁴O³:O¹,O^1′:O¹;2′:1:2κ⁴O¹:O¹,O^1′:O³] dihydrate], {[Pb(C₈H₄O₇S)(C₁₂H₈N₂)(H₂O)]·H₂O}_n, each seven‐coordinate lead(II) ion is bound by five O atoms from one water molecule and three 5‐sulfoisophthalate (sip) anions, and by two N atoms from a 1,10‐phenanthroline (phen) ligand. The sip sulfonate group is monodentate. One O atom of the sip carboxyl­ate group is chelated to one Pb²⁺ cation, with the other also bridging an adjacent Pb²⁺ cation. The carboxyl group is uncoordinated. This unusual coordination results in a chain structure along the b axis, which is linked by strong intermolecular hydrogen bonds into a three‐dimensional network.     

Polymeric μ‐cyano‐di­cyano­nickelate(II)‐μ‐cyano‐trans‐bis­[N‐(2‐hydroxyethyl)ethyl­enedi­amine]­cadmium(II)

The title compound, catena‐poly­[[μ‐cyano‐1:2κ²C:N‐di­cyano‐1κ²C‐trans‐bis­[N‐(2‐hydroxy­ethyl)­ethane‐1,2‐di­amine‐2κ²N,N′]­cadmium(II)­nickel(II)]‐μ‐cyano‐1:2′κ²C:N], [CdNi(CN)₄(C₄H₁₂N₂O)₂], consists of alternating square‐planar Ni(CN)₄ fragments, formally dianionic, and Cd(hydet‐en)₂ moieties [hydet‐en is N‐(2‐hydroxy­ethyl)­ethyl­ene­di­amine], with the two bridging cyanide ligands in a mutually trans disposition at the Ni atom and cis at the Cd atom. The resulting one‐dimensional zigzag chain structure has the Ni atom on an inversion center, while the distorted octahedron centered on the Cd atom lies on a twofold axis. The polymer chains are connected into undulating sheets by weak interchain N—H⋯N, N—H⋯O and O—H⋯N hydrogen bonds, which are also present between successive sheets.     

One‐dimensional CuII coordination polymers containing C2h‐symmetric 1,1′:4′,1′′‐terphenyl‐3,3′‐dicarboxylate linkers

Two new one‐dimensional Cu^II coordination polymers (CPs) containing the C_2h‐symmetric terphenyl‐based dicarboxylate linker 1,1′:4′,1′′‐terphenyl‐3,3′‐dicarboxylate (3,3′‐TPDC), namely catena‐poly[[bis(dimethylamine‐κN)copper(II)]‐μ‐1,1′:4′,1′′‐terphenyl‐3,3′‐dicarboxylato‐κ⁴O,O′:O′′:O′′′] monohydrate], {[Cu(C₂₀H₁₂O₄)(C₂H₇N)₂]·H₂O}_n, (I), and catena‐poly[[aquabis(dimethylamine‐κN)copper(II)]‐μ‐1,1′:4′,1′′‐terphenyl‐3,3′‐dicarboxylato‐κ²O³:O^3′] monohydrate], {[Cu(C₂₀H₁₂O₄)(C₂H₇N)₂(H₂O)]·H₂O}_n, (II), were both obtained from two different methods of preparation: one reaction was performed in the presence of 1,4‐diazabicyclo[2.2.2]octane (DABCO) as a potential pillar ligand and the other was carried out in the absence of the DABCO pillar. Both reactions afforded crystals of different colours, i.e. violet plates for (I) and blue needles for (II), both of which were analysed by X‐ray crystallography. The 3,3′‐TPDC bridging ligands coordinate the Cu^II ions in asymmetric chelating modes in (I) and in monodenate binding modes in (II), forming one‐dimensional chains in each case. Both coordination polymers contain two coordinated dimethylamine ligands in mutually trans positions, and there is an additional aqua ligand in (II). The solvent water molecules are involved in hydrogen bonds between the one‐dimensional coordination polymer chains, forming a two‐dimensional network in (I) and a three‐dimensional network in (II).     

A zigzag‐type one‐dimensional coordination polymer formed by (2,2‐di­methyl‐1,3‐propane­di­amine)­bis­(iso­nico­tin­ato)­platinum(II) and copper nitrate

The title compound, catena‐poly­[[[tri­aqua‐2κ³O‐(2,2‐dimethyl‐1,3‐propane­di­am­ine)‐1κ²N,N′‐μ‐isonicotinato‐1:2κ²N:O‐copper(II)­plati­num(II)]‐μ‐isonicotinato‐2:1′κ²O:N] dinitrate], {[CuPt(C₆H₄NO₂)₂(C₅H₁₄N₂)(H₂O)₃](NO₃)₂}_n, obtain­ed from equimolar (dmpda)Pt^II(isonic)₂ (where dmpda is 2,2‐di­methyl‐1,3‐propane­di­amine and isonic is isonicotinate) and copper(II) nitrate, has been found to be a one‐dimensional coordination polymer of the zigzag‐type.     

Cycloaddition Reactions of 7‐Benzylidenecycloocta‐1,3,5‐triene with Ethenetetracarbonitrile and 4‐Phenyl‐3H‐1,2,4‐triazole‐3,5(4H)‐dione

An (E)/(Z) mixture (3 : 2) of 7‐benzylidenecycloocta‐1,3,5‐triene ( 5 ) is obtained when 1‐benzylcycloocta‐1,3,5,7‐tetraene ( 7 ), prepared by an improved procedure, is treated with t‐BuOK in THF. Alternatively, a ca. 9 : 1 mixture (E)/(Z)‐ 5 can be prepared in a Wittig reaction involving benzaldehyde and cycloocta‐2,4,6‐trien‐1‐ylidenetriphenylphoshorane ( 9 ). Treatment of (E)/(Z)‐ 5 88 : 12 with ethenetetracarbonitrile (TCNE) gave a complex mixture of products, from which seven mono‐adducts and two bis‐adducts were isolated (Sect. 2.2.1). Of the mono‐adducts, four are π4+π2 adducts: two ((E)‐ and (Z)‐isomers) are derived from valence tautomers of the two isomers of (E)/(Z)‐ 5 , while it is tentatively suggested that the other two (again (E)‐ and (Z)‐isomers) are formed from the intermediacy of a pentadienyl zwitterion (Sect. 2.3). The remaining three mono‐adducts, two of which are epimers, are π8+π2 adducts. It is suggested that they are derived from the intermediacy of homotropylium zwitterions (Sect. 2.3). For the two bis‐adducts, it is postulated that they are derived from an initial π2+π2 cycloaddition involving the homotropylium zwitterions followed by π4+π2 cycloaddition to the valence tautomer of each of the π2+π2 cycloadducts. With 4‐phenyl‐3H‐1,2,4‐triazole‐3,5(4H)‐dione ( 6 ), (E)/(Z)‐ 5 91 : 9 yielded two π4+π2 cycloadducts ((E)‐ and (Z)‐isomers) as well as two epimeric π8+π2 cycloadducts (Sect. 2.2.2). The intermediacy of pentadienyl (tentative suggestion) and homotropylium zwitterions accounts for the formation of the products (Sect. 2.3).     

Synthesis and crystal structure of 10a‐oxo‐1‐phenylimino‐ 10‐propyl‐3,4,10,10a‐tetrahydro‐1H‐ 2‐thia‐4a,10‐diaza‐10aλ5‐ phospha‐phenanthren‐9‐one

The title novel fused tricyclic phosphoroheterocycle, C₁₉H₂₀N₃O₂PS, was synthesized in an excellent yield of 88.5% via the reac‐ tion of 1‐(2‐bromoethyl)‐2,3‐dihydro‐3‐propyl‐1,3,2‐benzodiazaphosphorin‐4(1H)‐one 2‐oxide with phenyl isothiocyanate, which contains the proximate imino and phosphoryl groups in the fused heterocycle. The crystallographic data analysis reveals that the title compound crystallizes into triclinic space group P with unit cell parameters: a = 9.159(3) Å, b = 10.463(4) Å, c = 10.698(4) Å, α = 88.090(6)°, β = 86.921(6)°, γ = 70.528(6)°, V = 965.0(6) ų for Z = 2 and there is a fused three‐ring in the molecule. The structure has been solved by direct methods and refined to R = 0.0424 for 2451 observed reflections with I >2 σ(I). The proximate imino and phosphoryl groups are not coplanar because both are jointly located in the fused heterocycle, thus having ring tension and this then destroys the conjugation between the CN and the PO moieties. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:671–676, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20169     

Bis[μ3‐cis‐N‐(2‐aminopropyl)‐N′‐(2‐carboxylatophenyl)oxamidato(3–)]bis(2,2′‐bipyridine)dichloridotetracopper(II) dihydrate

The title complex, bis[μ₃‐cis‐N‐(2‐aminopropyl)‐N′‐(2‐carboxylatophenyl)oxamidato(3−)]‐1:2:4κ⁷N,N′,N′′,O:O′,O′′:O′′′;2:3:4κ⁷O′′′:N,N′,N′′,O:O′,O′′‐bis(2,2′‐bipyridine)‐2κ²N,N′;4κ²N,N′‐dichlorido‐1κCl,3κCl‐tetracopper(II) dihydrate, [Cu₄(C₁₂H₁₂N₃O₄)₂Cl₂(C₁₀H₈N₂)₂]·2H₂O, consists of a neutral cyclic tetracopper(II) system having an embedded centre of inversion and two solvent water molecules. The coordination of each Cu^II atom is square‐pyramidal. The separations of Cu^II atoms bridged by cis‐N‐(2‐aminopropyl)‐N′‐(2‐carboxylatophenyl)oxamidate(3−) and carboxyl groups are 5.2096 (4) and 5.1961 (5) Å, respectively. A three‐dimensional supramolecular structure involving hydrogen bonding and aromatic stacking is observed.     

Depolymerization kinetics of di(4‐tert‐butyl cyclohexyl) itaconate and Mark‐Houwink‐Kuhn‐Sakurada parameters of di(4‐tert‐butyl cyclohexyl) itaconate and di‐n‐butyl itaconate

Multipulse pulsed laser polymerization coupled with size exclusion chromatography (MP‐PLP‐SEC) has been employed to study the depropagation kinetics of the sterically demanding 1,1‐disubstituted monomer di(4‐tert‐butylcyclohexyl) itaconate (DBCHI). The effective rate coefficient of propagation, k, was determined for a solution of monomer in anisole at concentrations, c, 0.72 and 0.88 mol L^?1 in the temperature range 0 ≤ T ≤ 70 °C. The resulting Arrhenius plot (i.e., ln k vs. 1/RT) displayed a subtle curvature in the higher temperature regime and was analyzed in the linear part to yield the activation parameters of the forward reaction. In the temperature region where no depropagation was observed (0 ≤ T ≤ 50 °C), the following Arrhenius parameters for k_p were obtained (DBCHI, E_p = 35.5 ± 1.2 kJ mol^?1, ln A_p = 14.8 ± 0.5 L mol^?1 s^?1). In addition, the k data was analyzed in the depropagatation regime for DBCHI, resulting in estimates for the associated entropy (?ΔS = 150 J mol^?1 K^?1) of polymerization. With decreasing monomer concentration and increasing temperature, it is increasingly more difficult to obtain well structured molecular weight distributions. The Mark Houwink Kuhn Sakurada (MHKS) parameters for di‐n‐butyl itaconate (DBI) and DBCHI were determined using a triple detection GPC system incorporating online viscometry and multi‐angle laser light scattering in THF at 40 °C. The MHKS for poly‐DBI and poly‐DBCHI in the molecular weight range 35–256 kDa and 36.5–250 kDa, respectively, were determined to be K_DBI = 24.9 (10³ mL g^?1), α_DBI = 0.58, K_DBCHI = 12.8 (10³ mL g^?1), and α_DBCHI = 0.63. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1931–1943, 2007     

catena‐Poly[potassium [copper(II)‐μ‐isothiocyanato‐μ‐N‐salicylidene‐β‐alaninato(2–)]]

The title polymeric compound, catena‐poly­[dipotassium [bis­[μ‐N‐salicyl­idene‐β‐alaninato(2−)]‐κ⁴O,N,O′:O′′;κ⁴O′′:O,N,O′‐dicopper(II)]‐di‐μ‐iso­thio­cyanato‐κ²N:S;κ²S:N], {K[Cu(NCS)(C₁₀H₉NO₃)]}_n, consists of [iso­thio­cyanato(N‐salicyl­idene‐β‐alaninato)copper(II)]⁻ anions connected through the two three‐atom thio­cyanate (μ‐NCS) and the two anti,anti‐μ‐­carboxyl­ate bridges into infinite one‐dimensional polymeric anions, with coulombically interacting K⁺ counter‐ions with coordination number 7 constrained between the chains. The Cu^II atoms adopt a distorted tetragonal–bipyramidal coordination, with three donor atoms of the tridentate Schiff base and one N atom of the bridging μ‐NCS ligand in the basal plane. The first axial position is occupied by a thio­cyanate S atom of a symmetry‐related μ‐NCS ligand at an apical distance of 2.9770 (8) Å, and the second position is occupied by an O atom of a bridging carboxyl­ate group from an adjacent coordination unit at a distance of 2.639 (2) Å.     

Gradual transformation of Ca(OH)<Subscript>2</Subscript> into CaCO<Subscript>3</Subscript> on cement hydration

The low temperature of decomposition of some calcium carbonates and the bending of the TG curves of hydrated cement between 500 and 800°C suggested the presence of some complex compound(s), which needed complementary investigation (XRD, TG). Stepwise transformation of portlandite (and/or lime) into calcium carbonate, with intermediate steps of calcium carbonate hydroxide hydrates (CCH-1 to CCH-5), was indicated by the previous study of two OPC. This was checked here on four cements ground for t _g=15, 20, 25 and 30 min and hydrated either in water vapour, successively at RH=1.0, 0.95 and 0.5 for 2 weeks each (WR1, WR2 and WR3, respectively) or as mortars in liquid water (1m), followed by WR as above. The d[001] spacing of portlandite was confirmed to vary: here between the lowest and the highest standard values. The diffractograms of n=32 different samples were analyzed for presence of standard CCH peaks, generally slightly displaced. These were: CCH-1 [Ca₃(CO₃)₂(OH)₂]: N=11 peaks, of three different d[hkl] spacings, CCH-2 [Ca₆(CO_2.65)₂(OH₆₅₇)₇(H₂O)₂]: N=10 for two d[hkl], CCH-3 [Ca₃(CO₃)₂(OH)₂·1.5H₂O]: N=14 for five d[hkl], CCH-4, ikaite [CaCO₃(H₂O)₆]: N=13 for six d[hkl], CCH-5[CaCO₃(H₂O)]: N=15 for five d[hkl]. Thus the most probable is the presence of the last three. The stepwise transformation of Ca(OH)₂ into CaCO₃ was confirmed: