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A new isoflavone, 4‘,5,7-trihydroxy-6,8-dimethylisoflavone (1), and a new sesterterpenoic acid (2), together with five known compounds, lichexanthone (3), (−)-pinoresinol (4), betulinic acid, palmitic acid, and β-sitosterol, were isolated from a dichloromethane extract of the branches of Henriettella fascicularis. Their structures were established by extensive spectroscopic methods. An attempt to determine the absolute stereochemistry of (2E,6S)-6-[(1R,5Z,3aS,9R,10Z,12aR)-1,2,3,3a,4,7,8,9,12,12a-decahydro-9-hydroxy-3a,6,10-trimethylcyclopentanocycloundecen-1-yl]-2-methylhept-2-enoic acid (2) was performed by single-crystal X-ray analysis, using Cu Kα radiation. Compound 1 showed significant competitive binding to estrogen receptor β and moderate antiestrogenic activity with cultured Ishikawa cells.

Four new sesquiterpenoid derivatives named mansonones N (1), O (2), P (3), and Q (4) were isolated from a dichloromethane extract of the heartwood of Mansonia gagei, a plant used in folk medicine in Thailand. Their structures were resolved on the basis of spectrometric data interpretation and the single-crystal X-ray analysis of 1 and 2.

This report concerns the organometallic chemistry of niobium based on a macrocyclic ligand. To this purpose, the (meso-octaalkylporphyrinogen)niobium(V) complex [(η⁵:η¹:η⁵:η¹-Et8N4)NbCl], 2, has been used as an appropriate starting material. The ionization of the Nb−Cl bond by the use of AgSO3CF3 gave a bifunctional acid−base system with an increased acidity of the metal center in [(η⁵:η¹:η¹:η¹-Et8N4)Nb(THF)(O3SCF3)], 3. The alkylation of 2 with LiMe gave a quite stable Nb(V) organometallic derivative [(η⁵:η¹:η¹:η¹-Et8N4)Nb−Me], 4, which undergoes a migratory insertion reaction with Bu^tNC leading to an η²-iminoacyl derivative [(η⁵:η¹:η¹:η¹-Et8N4)Nb(Bu^tNC)(η²-C(Me)&dbd;NBu^t)], 6 (νC&dbd;N, 2217 and 1736 cm^-1). Two steps of the reaction have been identified. An attempt to functionalize the Nb&dbd;O in [(η⁵:η¹:η¹:η¹-Et8(C4H2N)3(p-MeC5H2N)Nb&dbd;O], 7, by the use of LiMe led, on the contrary, to [(η¹:η¹:η¹:η¹-Et7(CH-Me)(C4H2N)3(p-MeC5H2N)NbOLi(THF)3], derived from the metalation of one of the meso-ethyl groups in 9. While X-ray analysis provided information on the solid state structures of 3, 4, 6, and 9, NMR studies allowed us to establish a relationship between the bonding mode of the porphyrinogen in the solid state and in solution.

The structural phase transitions between the intercalated and the non-intercalated phases of the layer structure compound n-decylammoniumchloride and n-hexylammoniumchloride have been studied via proton-14N and proton-35Cl nuclear quadrupole double resonance. The results have been related to an order-disorder model of the alkylammonium chains. The temperature dependence of the order parameters of the -NH3 head groups has been determined.

The coordination properties of [(η⁵-C5H5)Co{PR2(O)}3]^- (R = OEt (LOEt^-), Et (LEt^-)) toward Zr(IV) have been investigated and compared to related cyclopentadienyl complexes. Addition of 2 equiv of LOEt^- to [ZrCl4(THF)2] yields labile [Zr(LOEt)2Cl2] (2), which undergoes Arbuzov dealkylation to yield a dinuclear, seven-coordinate complex 1. Reaction of 2 with MeLi yields the metathesis product LiLOEt. Addition of 2 equiv of AgOTos to 2 affords octahedral [Zr(LOEt)2](OTos)2 (3). Reaction of [ZrCpCl3] with LOEt^- leads to Cp^- displacement to give [ZrLOEtCl3] (4). Addition of 2 equiv of LEt^- to [ZrCl4(THF)2] yields octahedral [Zr(LEt)2](Cl)2 (5). Compounds 1, 3, 4, and 5 have been characterized by X-ray crystallography.

Solubilization of the highly insoluble polymeric ZrCl4 is achieved using 1,2,4,5-Me4C6H2 (durene) as a carrier in a halogenated solvent, such as CH2Cl2, CHCl3, 1,2-Cl2C2H4, or o-Cl2C6H4. Solubilization can reach the level of 40 g of ZrCl4 in 100 mL of CH2Cl2 using an equimolar amount of durene. This is a very successful approach to making available soluble ZrCl4 in a noncoordinating solvent. The solubilization occurs via the formation of a η⁶-arene complex, which has been structurally characterized in the form of the hexamethylbenzene derivative [(η⁶-Me6C6)Zr2(μ-Cl)3Cl5] (3). This complex is in equilibrium, as revealed by the ¹H NMR spectrum in CH2Cl2, with free C6Me6 and a complex (4) which contains a higher Zr/C6Me6 ratio. A careful analysis of the CH2Cl2 solution, containing originally ZrCl4 and durene, showed that durene underwent transformation to C6Me5H and C6Me6. These species have been trapped, bonded to zirconium in complex [(η⁶-C6Me5R)Zr2(μ-Cl)3Cl5] (2, R = H, 50%; R = Me, 50%), which has been structurally characterized. The methyl redistribution reaction in CH2Cl2 can result in the inconvenient formation of byproducts derived from the Zr-assisted Friedel−Craft reaction of CH2Cl2 on the arene. The intermediate of such a reaction has been isolated as [C6Me6CHCl2]⁺[Zr2Cl9]^- (5), whose X-ray structure is available. In order to avoid the intervention of the solvent and to speed up the reaction, the ZrCl4 rearrangement of methylbenzenes was carried out in neat hydrocarbon at 90 °C for 6 h. This rearrangement has a number of peculiarities:  (i) unlike the original Jacobsen reaction, it involves intermolecular methyl transfer; (ii) it reaches an equilibrium of methyl distribution; and (iii) it is catalytic in zirconium. The very high stability of 3 accounts for the isolation of the same compound derived from the ZrCl4-assisted trimerization of 2-butyne in n-hexane.

An organic nonlinear optical crystal, 5-nitro-2-thiophenecarboxaldehyde-4-methylphenylhydrazone (NTMPH), has been prepared and investigated with regard to polymorphism, growth, and characterization of the structural and physical properties. Recrystallization of NTMPH in various solvents under different conditions showed the existence of three crystalline phases, red greenish plates (NTMPH−I) in space group P21/n, red orange prisms (NTMPH−II) in space group Pna21, and black needle (NTMPH−III) in space group P21/n. The crystal structures of NTMPH showed that three different intermolecular forces dominate the stabilization of one- or two-dimensional structures (called secondary structures in this work) of the three phases of the NTMPH crystals, namely the hydrogen bonding, dipole−dipole interactions, and the van der Waals forces for NTMPH−I, −II, and −III crystals, respectively. The thermal analysis showed that within the trimorphs the NTMPH−I crystal has the lowest thermodynamic stability with the lowest melting point and enthalpy, but NTMPH−II and −III crystals possess a higher thermodynamic stability and are called thermodynamic phases. The NTMPH−I crystal is easily crystallized in most conditions and is called a kinetic phase, whereas NTMPH−II and −III are crystallized with a higher supercooling (equal to a higher chemical potential), which also means that higher energy barriers for the nucleation of NTMPH−II and −III must be overcome. Since crystal structures cannot be designed precisely based on the molecular properties, especially for flexible molecules, the finding and selective growth of interesting polymorphic crystals is an essential step for the development of highly active nonlinear optical materials.