Novel rod-like [Cu(phen)2(OAc)]·PF6 complex for high-performance visible-light-driven photocatalytic degradation of hazardous organic dyes: DFT approach, Hirshfeld and fingerprint plot analysis.

A novel octahedral distorted coordination complex was formed from a copper transition metal with a bidentate ligand (1,10-Phenanthroline) and characterized by Ultraviolet-visible spectroscopy, Ultraviolet-visible diffuse reflectance spectroscopy, Fourier-transform infrared spectroscopy, Brunauer-Emmett-Teller, Field emission scanning electron microscopy, and Single-crystal X-ray diffraction. The Hirshfeld surface and fingerprint plot analyses were conducted to determine the interactions between atoms in the Cu(II) complex. DFT calculations showed that the central copper ion and its coordinated atoms have an octahedral geometry. The Molecular electrostatic potential (MEP) map indicated that the copper (II) complex is an electrophilic compound that can interact with negatively charged macromolecules. The HOMO-LUMO analysis demonstrated the π nature charge transfer from acetate to phenanthroline. The band gap of [Cu(phen)2(OAc)]·PF6 photocatalyst was estimated to be 2.88 eV, confirming that this complex is suitable for environmental remediation. The photocatalytic degradation of erythrosine, malachite green, methylene blue, and Eriochrome Black T as model organic pollutants using the prepared complex was investigated under visible light. The [Cu(phen)2(OAc)]·PF6 photocatalyst exhibited degradation 94.7, 90.1, 82.7, and 74.3 % of malachite green, methylene blue, erythrosine, and Eriochrome Black T, respectively, under visible illumination within 70 min. The results from the Langmuir-Hinshelwood kinetic analysis demonstrated that the Cu(II) complex has a higher efficiency for the degradation of cationic pollutants than the anionic ones. This was attributed to surface charge attraction between photocatalyst and cationic dyes promoting removal efficiency. The reusability test indicated that the photocatalyst could be utilized in seven consecutive photocatalytic degradation cycles with an insignificant decrease in efficiency.

Macropolyhedral syn-B18H22, the "Forgotten" Isomer.

The chemistry and physics of macropolyhedral B18H22 clusters have attracted significant attention due to the interesting photophysical properties of anti-B18H22 (blue emission, laser properties) and related potential applications. We have focused our attention on the "forgotten" syn-B18H22 isomer, which has received very little attention since its discovery compared to its anti-B18H22 isomer, presumably because numerous studies have reported this isomer as nonluminescent. In our study, we show that in crystalline form, syn-B18H22 exhibits blue fluorescence and becomes phosphorescent when substituted at various positions on the cluster, associated with peculiar microstructural-dependent effects. This work is a combined theoretical and experimental investigation that includes the synthesis, separation, structural characterization, and first elucidation of the photophysical properties of three different monothiol-substituted cluster isomers, [1-HS-syn-B18H21] 1, [3-HS-syn-B18H21] 3, and [4-HS-syn-B18H21] 4, of which isomers 1 and 4 have been proved to exist in two different polymorphic forms. All of these newly substituted macropolyhedral cluster derivatives (1, 3, and 4) have been fully characterized by NMR spectroscopy, mass spectrometry, single-crystal X-ray diffraction, IR spectroscopy, and luminescence spectroscopy. This study also presents the first report on the mechanochromic shift in the luminescence of a borane cluster and generally enriches the area of rather rare boron-based luminescent materials. In addition, we present the first results proving that they are useful constituents of carbon-free self-assembled monolayers.

A novel water-soluble thiosemicarbazone Schiff base ligand and its complexes as potential anticancer agents and cellular fluorescence imaging.

A novel fluorescent ligand (H2LCl⋅1.5CH3OH, 1) was synthesized and metal complexes of 1 with Mn(II), Fe(III), Ni(II), Cu(II), and Zn(II) were obtained as Mn(HL)2Cl2 (2), Fe(HL)2Cl3⋅3H2O (3), Ni(L)(HL)Cl⋅8H2O (4), Cu(HL)Cl2⋅4H2O (5), Zn(H2L)Cl3 (6), respectively. These compounds were identified by spectroscopic methods, elemental analysis, molar conductivity, and single-crystal X-ray crystallography. According to the crystal structure of 4 nickel (II), center is surrounded by two ligands in a distorted octahedral geometry. The ligand and its complexes are soluble in water and have excellent stability. In vitro anti-proliferative activity of these compounds was evaluated against human breast adenocarcinoma (MCF-7) and human lipo-sarcoma (SW-872) as cancer cells and human fibroblasts (HFF-2) as normal cells by MTT assay. Interestingly, complex 5 exhibited excellent activity against both cancer cells with low IC50 value 22.18 ± 0.35 µg/mL (35.66 ± 0.56 µM) for SW-872 and 79.41 ± 3.54 µg/mL (127.6 ± 5.69 µM) for MCF-7 among the compounds and in comparison with paclitaxel (PTX) which acts finely. Morphological changes were evaluated by flow cytometry that revealed apoptosis is the main cause of cell death. Likewise, cell cycle studies indicated the cell cycle arrest in the G1 and S phases for complex 5 against MCF-7 and SW-872 cancer cells, while complex 6 could arrest the MCF-7 and SW-872 cells in G2 and G1 phases, respectively. All of the compounds are fluorescent which enabled us to monitor the uptake and intracellular distribution in living human cancer cells by fluorescence microscopy.

Heteroleptic Silver(I) and Gold(I) N-Heterocyclic Carbene Complexes: Structural Characterization, Computational Analysis, Tyrosinase Inhibitory, and Biological Effects.

Derivatization of (NHC)M-Cl (M = Ag, Au) with selected sulfur donors from the family of dialkyldithiophosphates and bis(2-mercapto-1-methylimidazolyl)borate ligands gave a series of heteroleptic mononuclear complexes. In single-crystal X-ray diffraction analysis, Ag(I) complexes adopted a trigonal planar geometry, while Au(I) complexes are near-linear. TD-DFT and hole-electron analyses of the selected complexes gave insight into the electronic features of the metal complexes. In vitro cellular tests were conducted on the human cancerous breast cell line MCF-7 using 2 and 8. The antibacterial activities of complexes 1, 2, 3, 7, 8, and IPr-Ag-Cl were also screened against Gram-positive (Staphylococcus aureus PTCC 1112) and Gram-negative (Escherichia coli PTCC 1330) bacteria. Antityrosinase and hemolytic effects of the selected compounds were also determined.

Therapeutic potential of phospho-thiadiazole derivatives as anti-glioblastoma agents: synthesis, biological assessment and computational study.

In this study, three new phospho thiadiazole compounds (A, F and W) were investigated as possible cytotoxic agents. The compounds were synthesised and characterised by using spectroscopy methods. The crystal structure of compound A was investigated using X-ray crystallography, since the title compounds can exist as different tautomeric forms, their conformational and geometrical aspects were investigated computationally by the DFT method. NBO analysis suggested that these compounds can function as appropriate ligands for the reaction with the nitrogen bases of DNA. All the synthesised compounds were evaluated in vitro for their cytotoxic activities against cancer in the human glioblastoma cell lines (U-251) using the MTT assay. According to the annexin V-FITC/PI results, a combination of synthesised compounds with ReoT3D showed a synergistic effect to increase the percentage of apoptotic cells. Molecular docking study for A (the most toxic compound) showed how it interacts with DNA. Both in vitro and in silico results showed that A has promising inhibitory potential (IC50: 48.1 ± 0.3 µM) and binding energy (-6.67 kcal/mol).

Modulating the Inclusive and Coordinating Ability of Thiacalix[4]arene and Its Antenna Effect on Yb3-Luminescence via Upper-Rim Substitution.

The present work introduces the series of thiacalix[4]arenes (H4L) bearing different upper-rim substituents (R = H, Br, NO2) for rational design of ligands providing an antenna-effect on the NIR Yb3+-centered luminescence of their Yb3+ complexes. The unusual inclusive self-assembly of H3L- (Br) through Brπ interactions is revealed through single-crystal XRD analysis. Thermodynamically favorable formation of dimeric complexes [2Yb3+:2HL3-] leads to efficient sensitizing of the Yb3+ luminescence for H4L (Br, NO2), while poor sensitizing is observed for ligand H4L (H). X-ray analysis of the single crystal separated from the basified DMF solutions of YbCl3 and H4L(NO2) has revealed the transformation of the dimeric complexes into [4Yb3+:2L4-] ones with a cubane-like cluster structure. The luminescence characteristics of the complexes in the solutions reveal the peculiar antenna effect of H4L(R = NO2), where the triplet level at 567 nm (17,637 cm-1) arisen from ILCT provides efficient sensitizing of the Yb3+ luminescence.

One-Pot Synthesis of 2,5-Dihydrosiloles and Their Silole-Annulated Analogs Starting from Alkynylsilanes with a Terminal Alkynyl Group.

In contrast to the reaction of vinyl(alkynyl)silanes with 9-BBN-H, leading to the quantitative formation of 5-R-4-(9-BBN)-2,3-dihydro-1H-siloles, treatment of bis(alkynyl)silanes bearing one terminal alkynyl group with 2 equiv of 9-BBN-H followed by methanolysis afforded 5-R-4-(9-BBN)-2,5-dihydro-1H-siloles with yields of 85-90% (by NMR integration). The reaction proceeds via a double 1,2-hydroboration of the terminal triple bond with the formation of the geminal diborane followed by ring closure via intramolecular 1,1-carboboration of the remaining alkynyl fragment. Depending on the nature of the substituent R in position 5, the allylic BBN group locates in position 3 (R = Ph) or position 5 (R = SiHMe2, SiMe3) to give 2,3- or 2,5-dihydrosiloles, respectively. The protodeborylation of the allylic BBN group with MeOH of both 3,4-(9-BBN)2-2,3-dihydro- and 4,5-(9-BBN)2-2,5-dihydrosiloles results in the exclusive formation of 4-(9-BBN)-2,5-dihydrosiloles. In all cases, the formation of 10-12% of 2-R-2,4-(9-BBN)2-2,3-dihydrosilole minor isomers has been observed, which occurs from vicinal diboranes formed as side products by a second hydroboration of the terminal triple bond. Similarly, treatment of the tri- and tetraalkynes containing a terminal triple bond with 2 equiv of 9-BBN-H followed by treatment with methanol resulted in the high-yield formation of 1,2,6,6a-tetrahydro-1,6-disilapentalenes and 2,6,7,7a-tetrahydro-1,6,7-trisila-1H-cyclopenta[a]pentalenes, respectively.

A Reversible NO-Triggered Multiple Metallaborane Cluster Fusion by Ligand Expulsion/Addition from (PMe2Ph)4Pt2B10H10 to Afford (PMe2Ph)8Pt8B40H40 and (PMe2Ph)5Pt4B20H20.

The dimetallic boron hydride cluster, (PMe2Ph)4Pt2B10H10 (1-Pt2), is known to reversibly sequester small molecules (e.g., O2, CO, and SO2) across its Pt-Pt cluster vector. Here, we report the very different effect of the addition of nitric oxide (NO) to solutions of (1-Pt2) that prompts the elimination of some of its phosphine ligands and the autofusion of the resultant {(PMe2Ph)xPt2B10H10} units to afford the metallaborane conglomerates (PMe2Ph)8Pt8B40H40 (2-Pt8, 38%) and (PMe2Ph)5Pt4B20H20 (3-Pt4, 34%). Single-crystal X-ray studies of these multicluster assemblies reveal the links between the clusters to be a combination of both Pt-Pt bonds and Pt-µH-B 2-electron, 3-center bonds in (2-Pt8) and Pt-µH-B 2-electron, 3-center bonds in (3-Pt4). For compound (2-Pt8), the cluster assemblage can be effectively reversed by the addition of ethyl isonitrile (EtNC) to afford (EtNC)3(PMe2Ph)2Pt2B10H10 4 in quantitative yield. The compounds were characterized by mass spectrometry, multielement NMR spectroscopy, and single-crystal X-ray diffraction studies.

Isolation, spectroscopic characterization, X-ray, theoretical studies as well as in vitro cytotoxicity of Samarcandin.

Samarcandin 1, a natural sesquiterpene-coumarin, was isolated as well as elucidated from F. assa-foetida which has significant effect in Iranian traditional medicine because of its medicinal attitudes. The crystal structure of samarcandin was determined by single-crystal X-ray structure analysis. It is orthorhombic, with unit cell parameters a=10.8204 (5)Å, b=12.9894 (7)Å, c=15.2467 (9)Å, V=2142.9 (2)Å(3), space group P212121 and four symmetry equivalent molecules in the unit cell. Samarcandin was isolated in order to study for its theoretical studies as well as its cellular toxicity as anti-cancer drug against two cancerous cells. In comparison with controls, our microscopic and MTT assay data showed that samarcandin suppresses cancer cell proliferation in a dose-dependent manner with IC50=11µM and 13 for AGS and WEHI-164 cell lines, respectively. Density functional theory (DFT) and time-dependent density functional theory (TD-DFT) of the structure was computed by three functional methods and 6-311++G(∗∗) standard basis set. The optimized molecular geometry and theoretical analysis agree closely to that obtained from the single crystal X-ray crystallography. To sum up, the good correlations between experimental and theoretical studies by UV, NMR, and IR spectra were found.

Synthesis and characterization of a helicene-based imidazolium salt and its application in organic molecular electronics.

Herein we demonstrate the synthesis of a helicene-based imidazolium salt. The salt was prepared by starting from racemic 2-methyl[6]helicene, which undergoes radical bromination to yield 2-(bromomethyl)[6]helicene. Subsequent treatment with 1-butylimidazole leads to the corresponding salt 1-butyl-3-(2-methyl[6]helicenyl)-imidazolium bromide. The prepared salt was subsequently characterized by using NMR spectroscopy and X-ray analysis, various optical spectrometric techniques, and computational chemistry tools. Finally, the imidazolium salt was immobilized onto a SiO2 substrate as a crystalline or amorphous deposit. The deposited layers were used for the development of organic molecular semiconductor devices and the construction of a fully reversible humidity sensor.

Synthesis and structural/physical properties of U3Fe2Ge7: a single-crystal study.

A single crystal of U3Fe2Ge7 was synthesized by the tin-flux method, and its structural and electronic properties were studied. The compound crystallizes in the orthorhombic crystal structure of La3Co2Sn7 type with two Wyckoff sites for the U atoms. U3Fe2Ge7 displays a ferromagnetic order below TC = 62 K. Magnetization measurements in static (up to 14 T) and pulsed (up to 60 T) magnetic fields revealed a strong two-ion uniaxial magnetic anisotropy. The easy magnetization direction is along the c axis and the spontaneous magnetic moment is 3.3 µB per formula unit at 2 K. The moment per Fe atom is 0.2 µB, as follows from Mössbauer spectroscopy. The magnetic moments are oriented perpendicular to the shortest inter-uranium distances that occur within the zigzag chains in the ab plane, contrary to other U-based isostructural compounds. The magnetization along the a axis reveals a first-order magnetization process that allows for a quantitative description of the magnetic anisotropy in spite of its enormous energetic strength. The strong anisotropy is reflected in the specific heat and electrical resistivity that are affected by a gap in magnon spectrum.

A γ-cyclodextrin duplex connected with two disulfide bonds: synthesis, structure and inclusion complexes.

Per(2,3,6-tri-O-benzyl)-γ-cyclodextrin was debenzylated by DIBAL-H to produce a mixture of C6(I),C6(IV) and C6(I),C6(V) isomeric diols, which were separated and isolated. The C2-symmetrical C6(I),C6(V) diol was transformed into dithiol and dimerized to produce a γ-cyclodextrin duplex structure. A crystal structure revealed tubular cavity whose peripheries are slightly elliptically distorted. The solvent accessible volume of the cavity of the γ-CD duplex is about 740 Å(3). Due to this large inner space the duplex forms very stable inclusion complexes with steroids; bile acids examined in this study show binding affinities to the γ-cyclodextrin duplex in the range of 5.3 × 10(7) M(-1)-1.9 × 10(8) M(-1).

Biochemical and biophysical properties of a novel homoisoflavonoid extracted from Scilla persica HAUSSKN.

In this study isolation and structural elucidation of a homoisoflavonoid, 3-(3',4'-dihydroxybenzyl)-8-hydroxy-5,7-dimethoxychroman-4-one (Scillapersicone 1), is reported from Scilla persica HAUSSKN. The structure was solved by a single crystal X-ray analysis. The unit cell parameters are a=11.7676 (2)Å, b=20.1174 (4)Å, c=7.8645 (9)Å, ß=93.544 (2)°, V=1858.23 (7)Å(3), monoclinic space group P21/c and four symmetry equivalent molecules in an unit cell. The structure was consistent with the UV, IR, 1D and 2D NMR, HRFAB-MS data. The optimized molecular geometry agrees closely that obtained from the single crystal X-ray crystallography. Furthermore, cytotoxicity of this compound was evaluated by MTT assay on AGS and WEHI-164 cancerous cell lines.

Introducing Novel Redox-Active Bis(phenolate) N-Heterocyclic Carbene Proligands: Investigation of Their Coordination to Fe(II)/Fe(III) and Their Catalytic Activity in Transfer Hydrogenation of Carbonyl Compounds.

A simple and efficient procedure for synthesizing novel pincer-type tridentate N-heterocyclic carbene bisphenolate ligands is reported. The synthesis of pincer proligands with N,N'-disubstituted imidazoline core, 5 and 6, was carried out via triethylorthoformate-promoted cyclization of either N,N'-bis(2-hydroxy-3,5-di-tert-butylphenyl)cyclohexanediamine, 3, or N,N'-bis(2-hydroxyphenyl)cyclohexanediamine, 4, in the presence of concentrated hydrochloric acid. Cyclic voltammograms of the ligands revealed ligand-centered redox activity, indicating the noninnocent nature of the ligands. The voltammograms of the ligands exhibit two successive one-electron oxidations and two consecutive one-electron reductions. In contrast to previous reports, the redox-active ligands in this study exhibit one-electron oxidation and reduction processes. All products were thoroughly characterized by using 1H and 13C NMR spectroscopy. The base-promoted deprotonation of the proligands and subsequent reaction with iron(II) and iron(III) chlorides yielded compounds 7 and 8. These compounds are binuclear and tetranuclear iron(III) complexes that do not contain carbene functional groups. Complexes 7 and 8 were characterized by using elemental analysis and single-crystal X-ray crystallography. At low catalyst loadings, both 7 and 8 exhibited high catalytic activity in the transfer hydrogenation of selected aldehydes and ketones.

Synthetic routes to carbon substituted cobalt bis(dicarbollide) alkyl halides and aromatic amines along with closely related irregular pathways.

Carbon substituted cobalt bis(dicarbollide) alkyl halides [(1-X-(CH2)n-1,2-C2B9H10)(1,2-C2B9H11)-3,3'-Co]Me4N (X = Br, I; n = 1-3) are prepared in high yields (>90%) from their corresponding alcohols without side skeletal substitutions. These species offer access to the synthesis of aromatic cobalt bis(dicarbollide) amines, however only for particular terminal halogen substitution, the propylene pendant arm, and under appropriately controlled reaction conditions. Thus, the compounds substituted at cage carbon atoms with a propylene linker and terminal aromatic amine groups could be prepared. In other cases, numerous irregular reaction pathways occur, undoubtedly as a consequence of the bulky anionic boron cage in close proximity to the reaction site. Among them, an unusual intramolecular hydroboration forming rigidified carbon-to-boron bridged isomeric anions with an asymmetric structure that correspond to formulae [(1,8'-µ-C2H4)-(1,2-C2B9H10)(1',2'-C2B9H10)-3,3'-Co]- and [(1,7'-µ-C2H4)-(1,2-C2B9H10)(1',2'-C2B9H10)-3,3'-Co]- is described herein and the former isomer is structurally characterized. This product with a restrained geometry is widely accessible through nucleophile and/or thermally induced decomposition of (pseudo)halides attached to the cage via an ethylene linker. Surprisingly enough, also doubly bridged isomeric species [(1,8-µ-C2H4-1,2-C2B9H9)2-3,3'-Co]- and [(1,7-µ-C2H4-1,2-C2B9H9)2-3,3'-Co]- are available in good yield using these methods. Furthermore, other more typical side reactions are discussed, i.e. nucleophilic reactions of propyl halides with Me3N formed apparently by disproportionation of Me4N+ at higher temperatures or with pyridine used as a base.

Correction: Synthetic routes to carbon substituted cobalt bis(dicarbollide) alkyl halides and aromatic amines along with closely related irregular pathways.

Correction for 'Synthetic routes to carbon substituted cobalt bis(dicarbollide) alkyl halides and aromatic amines along with closely related irregular pathways' by Jan Nekvinda et al., Dalton Trans., 2024, 53, 5816-5826, https://doi.org/10.1039/D4DT00072B.

Low-dimensional compounds containing cyanide groups. XXVI. (Dicyanamido-κN(1))bis(5,5'-dimethyl-2,2'-bipyridine-κ(2)N,N')copper(II) complexes with tetrafluoroborate and perchlorate anions.

(Dicyanamido-κN(1))bis(5,5'-dimethyl-2,2'-bipyridine-κ(2)N,N')copper(II) tetrafluoroborate, [Cu{N(CN)2}(C12H12N2)2]BF4, (I), and (dicyanamido-κN(1))bis(5,5'-dimethyl-2,2'-bipyridine-κ(2)N,N')copper(II) perchlorate, [Cu{N(CN)2}(C12H12N2)2]ClO4, (II), are isomorphous and consist of [Cu{N(CN)2}(mbpy)2](+) cations (mbpy is 5,5'-dimethyl-2,2'-bipyridine) and BF4(-) or ClO4(-) anions, respectively. The Cu(II) cations in both structures are five-coordinated in distorted trigonal bipyramidal environments by four N atoms of two mbpy ligands and one N atom of the dicyanamide anion, which is coordinated in a monodentate manner in the equatorial plane, with Cu-N distances of 1.980 (3) and 1.977 (2) Šin (I) and (II), respectively. The two axial Cu-Nmbpy bonds have very similar values [1.986 (1) Šon average] and are shorter than the other two equatorial Cu-Nmbpy bonds. These have different values in the individual compounds but nevertheless form two pairs of similar bonds in (I) and (II) [2.066 (8) and 2.112 (2) Å, respectively, on average]. Besides the ionic forces in both structures, the structures are stabilized by C-H...N and C-H...X hydrogen bonds (X = F and O, respectively), and by π-π interactions between the pyridine rings of neighbouring mbpy molecules.

A novel amido-pyrophosphate Mn(II) chelate complex with the synthetic ligand O{P(O)[NHC(CH3)3]2}2 (L): [Mn(L)2{OC(H)N(CH3)2}2]Cl2·2H2O.

The title complex, trans-bis(dimethylformamide-κO)bis{N,N'-N'',N'''-tetra-tert-butyl[oxybis(phosphonic diamide-κO)]}manganese(II) dichloride dihydrate, [Mn(C16H40N4O3P2)2(C3H7NO)2]Cl2·2H2O, is the first example of a bis-chelate amido-pyrophosphate (pyrophosphoramide) complex containing an O[P(O)(NH)2]2 fragment. Its asymmetric unit contains half of the complex dication, one chloride anion and one water molecule. The Mn(II) atom, located on an inversion centre, is octahedrally coordinated, with a slight elongation towards the monodentate dimethylformamide ligand. Structural features of the title complex, such as the P=O bond lengths and the planarity of the chelate ring, are compared with those of previously reported complexes with six-membered chelates involving the fragments C(O)NHP(O), (X)NP(O) [X = C(O), C(S), S(O)2 and P(O)] and O[P(O)(N)2]2. This analysis shows that the six-membered chelate rings are less puckered in pyrophosphoramide complexes containing a P(O)OP(O) skeleton, such as the title compound. The extended structure of the title complex involves a linear aggregate mediated by N-H...O and N-H...Cl hydrogen bonds, in which the chloride anion is an acceptor in two additional O-H...Cl hydrogen bonds.

New rac-XP(O)(OC6H5)(NHC6H4-p-CH3) [X = N(CH3)(cyclo-C6H11) and NH(C3H5)] and rac-(C6H5CH2NH)P(O)(OC6H5)(NH-cyclo-C6H11) mixed-amide phosphinates.

The mixed-amide phosphinates, rac-phenyl (N-methylcyclohexylamido)(p-tolylamido)phosphinate, C20H27N2O2P, (I), and rac-phenyl (allylamido)(p-tolylamido)phosphinate, C16H19N2O2P, (II), were synthesized from the racemic phosphorus-chlorine compound (R,S)-(Cl)P(O)(OC6H5)(NHC6H4-p-CH3). Furthermore, the phosphorus-chlorine compound ClP(O)(OC6H5)(NH-cyclo-C6H11) was synthesized for the first time and used for the synthesis of rac-phenyl (benzylamido)(cyclohexylamido)phosphinate, C19H25N2O2P, (III). The strategies for the synthesis of racemic mixed-amide phosphinates are discussed. The P atom in each compound is in a distorted tetrahedral (N(1))P(=O)(O)(N(2)) environment. In (I) and (II), the p-tolylamido substituent makes a longer P-N bond than those involving the N-methylcyclohexylamido and allylamido substituents. In (III), the differences between the P-N bond lengths involving the cyclohexylamido and benzylamido substituents are not significant. In all three structures, the phosphoryl O atom takes part with the N-H unit in hydrogen-bonding interactions, viz. an N-H···O=P hydrogen bond for (I) and (N-H)(N-H)···O=P hydrogen bonds for (II) and (III), building linear arrangements along [001] for (I) and along [010] for (III), and a ladder arrangement along [100] for (II).