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Double-decker complexes based on single-molecule magnets (SMMs) are a class of highly promising molecules for applications in molecular spintronics, wherein control of both the ligand oxidative states and the 2D supramolecular structure on carbon materials is of great importance. This study focuses on the synthesis and study of 2,3,7,8,12,13,17,18-octaethylporphyrin (OEP)-Tb(III) double-decker complexes with different electronic structures comprising protonated, anionic, and radical forms. Magnetic susceptibility measurements revealed that only the anionic and radical forms of the OEP-Tb(III) double-decker complexes exhibited SMM properties. The barrier heights for magnetic moment reversal were estimated to be 207 and 215 cm(-1) for the anionic and radical forms, respectively. Scanning tunneling microscopy (STM) investigations revealed that these OEP-Tb(III) complexes form well-ordered monolayers upon simple dropcasting from dilute dichloromethane solutions. All three complexes form an isomorphic pseudo-hexagonal 2D pattern, regardless of the differences in the electronic structures of their porphyrin-Tb cores. This finding is of interest for SMM technology as ultrathin films of these materials undergoing chemical transformations will not require any detrimental reorganization. Finally, we demonstrate self-assembly of the protonated 5,15-bisdodecylporphyrin (BDP)-Tb(III) double-decker complex as an example of successful supramolecular design to achieve controlled alignment of SMM-active sites.

Four different porphyrin-imide dyads bearing different central metals (zinc or rhodium) and different substituents on the porphyrin macrocycles (tert-butyl or methoxy) were synthesized for single molecular diode measurements. The molecules were designed to separate the donor component (porphyrin) from the acceptor component (imide) by bonding in a perpendicular arrangement, thus enhancing the rectification properties. UV/Vis absorption spectra and density functional theory calculations showed that the design was successful and that the molecular orbitals of the dyads were the summation of the two components, with minimal interaction between them. The effect of the central metal was found to be significant, with the lowest energy absorption for the zinc dyads being attributed to the mixed state of charge transfer from porphyrin to imide and the Q band, whereas that of the rhodium dyads indicated insignificant charge-transfer character.

N-Confused tetraarylporphyrinatoantimony(V) dimethoxides were synthesized and their X-ray crystallographic structure, absorption spectra and voltammetric spectra were studied. X-ray crystallographic structure revealed neutral molecules with no counter anion. From the absorption spectra and voltammetric studies we estimated their energy gaps to be about 0.2 eV less than the corresponding porphyrinatoantimony(V). The axial ligands could easily be exchanged in solvent alcohol by acid promotion. These characteristics of N-confused porphyrinatoantimony(V) indicate that they are good candidates for the molecular wire component.

The syntheses and X-ray structures of novel porphyrinoids, “N-fused porphyrins (NFPs)”, and their reactivity were described. NFP was spontaneously produced from the bromo-substituted N-confused tetraarylporphyrin in a pyridine solution at room temperature. X-ray diffraction analyses revealed that the porphyrinoid core containing a fused tri-pentacyclic ring is almost planar. The deviation from the mean plane of 4e‘, for example, was within 0.30 A. The peripheral aryl substituents were tilted 50.4, 53.5, 64.4, and 12.4° relative to the porphyrin mean plane, respectively. The occurrence of a three-centered hydrogen bonding in the NFP core was inferred by the downfield shift of the inner NH signal (e.g., 8.48 ppm for 4e‘) in 1H NMR and the short distances (within 2.4−2.9 A) among the inner core nitrogens, N2, N3, and N4. The optical absorption spectra of NFPs exhibit Soret-like transitions around 360, 500, and 550 nm and weak Q-like bands around 650, 700, 850, and 940 nm in CH2Cl2. The electrode process of 4...

The synthesis, characterization, and X-ray structure of the first example of an air-stable silver(III) complex of an N-confused tetraphenylporphyrin (5,10,15,20-tetraphenyl-2-aza-21-carbaporphyrin argentate(III) or Ag(III)NCTPP, 7) is reported. Crystals of Ag(III)NCTPP·CH2Cl2 belong to the monoclinic space group P21/c (No. 14), with a = 9.038(4) A, b = 15.097(3) A, c = 25.578(8) A, β = 91.32(3)°, and Z = 4. The lengths (A) of the three silver−nitrogen and one silver−carbon bonds are inequivalent [Ag−N(1), 2.06(2); Ag−N(2), 2.08(2); Ag−N(3), 2.03(2); and Ag−C(17), 2.04(2)], reflecting the asymmetric structure of the NCTPP ligand. The very small distortion from a square planar geometry is shown in N−Ag−N and N−Ag−C angles (degrees): N(1)−Ag−N(2), 89.7(8); N(1)−Ag−N(3), 179(1); N(1)−Ag−C(17), 90.3(9); N(2)−Ag−N(3), 89.6(9); N(2)−Ag−C(17), 179(1); and N(3)−Ag−C(17), 90.9(1). The diamagnetic nature of Ag(III)NCTPP was confirmed by 1H and 13C NMR and magnetic susceptibility measurements. Electrochemical and sp...

The metal ion determines the reactivity upon electrochemical oxidation of metal porphyrins that are unsubstituted at the meso position. Thus, with Cu2+, Pd2+, and Ni+2 as the central ion (and for the free porphyrin base), directly linked meso,β porphyrin dimers 2 were formed, while Mg and Zn complexes afforded the corresponding directly linked meso,meso porphyrin dimers 1. Ar=3,4-tBu2C6H3.

Novel porphyrins substituted with aryl and nitro substituents at the β-position were prepared by the tetramerization of 2-hydroxymethyl-3-aryl-4-nitropyrroles. Aggregation properties of these porphyrins are investigated by means of UV–VIS, 1H-NMR and EPR spectroscopy. Porphyrin 4a substituted with 4-methoxyphenyl and nitro groups was found to form a strong cofacial aggregate in solution (K = 900–1300 dm3 mol–1). The extent of aggregation decreases in the following order: porphyrin 4a (nitro and 4-methoxyphenyl substituents) > 4b (nitro and phenyl substituents) > TMTP (methyl and phenyl substituents) > OEP (ethyl substituents). EPR spectra of Cu–4a support the dimer structure of 4a, and the distance between two porphyrins is estimated to be about 4 A.

3,4-Diarylpyrroles (1) have been directly prepared in 20–50% yield by the reaction of β-nitrostyrenes with aqueous TiCl3 in 1,4-dioxane. Pyrroles 1 were also prepared via Barton–Zard pyrrole synthesis using the reaction of α-nitrostilbenes with ethyl isocyanoacetate followed by de-ethoxycarbonylation. 3,4-Diarylpyrroles have been converted into dodecaarylporphyrins by reaction with aromatic aldehydes. Various aryl groups are readily introduced at the periphery of porphyrins by this method. Phenyl substitution at any of the positions of pyrroles decreases Eox1/2, while E1/2red is almost unchanged. On the other hand, substitution of the 2-thienyl group affects both the HOMO and LUMO energies, and the UV-vis spectra of dodeca-2-thienylporphyrins (4f or 4i) are extremely red-shifted.

New types of macrocyclic ligands with tetraoxa[n.n]metacyclophane molecular skeletons have been synthesized. The structures of 14,28-dibromo-1,8,15,22-tetraoxa[8.8]metacyclophane 2a, 16,32-dibromo-1,10,17,26-tetraoxa[10.10]metacyclophane 2b, 14,28-dibromo-2,7,16,21-tetraoxa[8.8]metacyclophane 3a, 16,32-dibromo-2,9,18,25-tetraoxa[10.10]metacyclophane 3c, 18,36-dibromo-2,11,20,29-tetraoxa[12.12]metacyclophane 3d, 20,40-dibromo-2,13,22,33-tetraoxa[14.14]metacyclophane 3e and 14,28-diiodo- 2,7,16,21-tetraoxa[8.8]metacyclophane 9a have been determined by single-crystal X-ray structure analyses. In compounds 2a and 2b, two bromide atoms face each other within the macrocyclic ring while in compounds 3c, 3d and 3e the bromine atoms face in opposite directions, outwards from the macrocyclic ring. In the smaller ring compounds 3a and 9a the structure was intermediate between these two types.Substitution of the bromine atoms via lithiation has been achieved smoothly with iodine and methyl iodide as the electrophiles to afford disubstituted compounds in good yields, while with trimethylsilyl chloride as the electrophile the mono-substituted compound has been obtained.

6,13-Dihydro-6,13-ethanopentacene-15,16-dione gave pentacene efficiently both in solid and in solution by irradiation of light.

Nitre heteroarenes react with ethyl isocyanoacetate in the presence of 1,8-diazabicyclo[5.4.0]undecene (DBU) to give pyrroles or pyrimidine N-oxide depending on the structure of the starting nitro compounds. For example, 4-nitro-2,1,3-benzothiadiazole 3a reacted with ethyl isocyanoacetate to give ethyl 2,1,3-benzothiadiazole[3,4-c]pyrrole-2-carboxylate 4a (33%), while a similar reaction with 5-nitro-2,1,3-benzothiadiazole 3b gave the corresponding compound 4b (21%) as a sole product. A plausible mechanism for these reactions is presented.

Pyrroles fused with crown ethers are prepared by the reaction of 3,4-dihydroxy pyrrole 1 and polyethylene glycol ditosylate 2 in the presence of cesium fluoride using a convenient high dilution method. These pyrroles can be converted into the corresponding porphyrins with four crown ether moieties, which are expected to form ion channels.

Pyrroles substituted with long alkoxy groups are prepared by the reaction of iminodiacetic acid dimethyl ester and dimethyl oxalate and the subsequent alkylation. These pyrroles are good precursor molecules for the corresponding porphyrins, which are expected to form an ordered columnar mesophase and are able to co-ordinate to various metals.

Organic functional materials are utilized in commonly used electronic products such as organic light emitting diodes and liquid crystals in cellular phones and televisions. Currently, materials are used in mass and most of their characteristic properties arise from the cooperative interaction of a number of molecules or atoms. As the result, many physical properties disappear when the size of the material becomes smaller than a certain size. For example, ferromagnetism is observed in larger samples than ca. 15 nm in diameter because collaboration of many spins in the sample is required for the property. As the result, the density of memory size in hard disk is limited to ca. 3 TB/in2 with ordinal magnetic materials. If the single molecules can work as magnets, the density can increase to 600 TB/in2 theoretically. Molecules which can work as magnets in single molecule are called single molecule magnet, and first found as a Mn12 cluster by Sessoli et al., in 1993.1 During the last two decades, polymetallic transition-metal complexes with strong intramolecular exchange coupling have been typical research targets because their high-spin ground state and large anisotropy may impart a higher energy barrier than that of single–metal-ion complexes. Since Ishikawa reported SMMs based on single lanthanide ions in 2003,2 many mononuclear complexes with slow magnetic relaxation have been reported. In particular, phthalocyanine (Pc) Tb double-decker compounds display a higher blocking temperature, below which magnetic relaxation is slow. Moreover, the magnetic relaxation behavior of double-decker complexes is sensitive to their coordination mode, which can be easily tuned through their flexible structure. This variation in the coordination modes makes it possible to control their magnetic properties via external stimuli such as a redox reaction or pulse current from an STM chip, resulting in unique switching properties. A tetraphenylporphyrin (TPP) Tb double-decker complex was synthesized, and the crystal structures of both the protonated and deprotonated forms have been determined. The structure analysis demonstrated for the first time in tetrapyrrole-based double-decker complexes that a proton is localized on the pyrrole ring nitrogen for charge balance. The AC magnetic susceptibility measurements revealed that the protonated form does not show SMM behavior although the anionic form does act as an SMM. The SMM behavior of the double-decker complex can be reversibly switched through only a single proton.3,4 We studied the synthesis and study of octaethylporphyrin (OEP) Tb double-decker complexes with different electronic structures comprising protonated, anionic, and radical forms. Magnetic susceptibility measurements revealed that only the anionic and radical forms of the OEP Tb double-decker complexes exhibited SMM properties. Scanning tunneling microscopy (STM) investigations revealed that these OEP Tb complexes form well-ordered monolayers upon simple dropcasting from dilute dichloromethane solutions. All three complexes form an isomorphic pseudo-hexagonal 2D pattern, regardless of the differences in the electronic structures of their porphyrin-Tb cores. This finding is of interest for SMM technology since chemical transformations in ultrathin films of these materials will not require any detrimental reorganization.5 Further, we effect sub-molecular scale patterning to create an ordered assembly of SMMs by using (OEP)-Tb double-decker complex, Tb(OEPH)(OEP)), which exhibits non-SMM properties but changes into the SMM molecule Tb(OEP)2 by discharging a hydrogen atom. We locally formed an SMM molecule Tb(OEP)2 by injecting tunneling electrons using scanning tunneling spectroscopy (STS) on the ordered film of Tb(OEPH)(OEP), where the spin of the converted Tb (OEP)2 molecule was detected by a Fano dip of Kondo resonance in scanning tunneling spectroscopy. Single molecular conductance of Tb(TPP)2 and Tb(TPP)(Phthalocyanine) complexes were also studied using break-junction methods to show that in the later complex the conductance changed greatly by deprotonation. REFERENCES. (1) Sessoli, R.; Gatteschi, D.; Caneschi, A.; Novak, M. A. Nature 1993, 365, 141. (2) Ishikawa, N.; Sugita, M.; Ishikawa, T.; Koshihara, S.; Kaizu, Y. J. Am. Chem. Soc. 2003, 125, 8694. (3) Tanaka, D.; Inose, T.; Tanaka, H.; Ishikawa, N.; Ogawa, T. Chem. Commun. 2012, 7796. (4) Inose, T.; Tanaka, D.; Ogawa, T. Heterocycles 2012, 86, 1549. (5) Inose, T.; Tanaka, D.; Tanaka, H.; Ivasenko, O.; Nagata, T.; Ohta, Y.; De Feyter, S.; Ishikawa, N.; Ogawa, T. Chem. Eur. J. 2014, 20, 11362.

Single-walled carbon nanotube (SWNT) was physically adsorbed by several kinds of particles including porphyrin, naphthalenediimide (NDI) and polyoxometalate (POM). Nanoscale electrical properties of the complexes were measured by point-contact current imaging atomic force microscopy (PCI-AFM), and rectification appeared at the interface of particle and SWNT. Rectification ratio (RR) and plateau width (PW) could be controlled by the particle size of NDI. Reversible rectification direction was observed in the case of POM. Charge transfer between SWNT (Pt cantilever) and nanoparticle was considered as the reason of rectification.

A tetraphenylporphyrin based Tb(III) double-decker complex has been synthesized and the crystal structure of both protonated and deprotonated forms has been determined. The ac magnetic susceptibility measurements revealed that the SMM properties of the double-decker complex can be reversibly switched by only a single proton.

A polyhistidine (His) tag was fused to the C- or N-terminus of the light-harvesting (LH1)-α chain of the photosynthetic antenna core complex (LH1-RC) from Rhodobacter sphaeroides to allow immobilization of the complex on a solid substrate with defined orientation. His-tagged LH1-RCs were adsorbed onto a gold electrode modified with Ni-NTA. The LH1-RC with the C-terminal His-tag (C-His LH1-RC) on the modified electrode produced a photovoltaic response upon illumination. Electron transfer is unidirectional within the RC and starts when the bacteriochlorophyll a dimer in the RC is activated by light absorbed by LH1. The LH1-RC with the N-terminal His-tag (N-His LH1-RC) produced very little or no photocurrent upon illumination at any wavelength. The conductivity of the His-tagged LH1-RC was measured with point-contact current imaging atomic force microscopy, indicating that 60% of the C-His LH1-RC are correctly oriented (N-His 63%). The oriented C-His LH1-RC or N-His LH1-RC showed semiconductive behavior, that is, had the opposite orientation. These results indicate that the His-tag successfully controlled the orientation of the RC on the solid substrate, and that the RC produced photocurrent depending upon the orientation on the electrode.

In marked contrast to previously studied triarylbismuthanes, tris-(2,6-dimethoxyphenyl)bismuthane 1f showed itself to be a nucleophile strong enough to react with some activated alkyl halides via the probable formation of a bismuthonium intermediate. On the basis of X-ray crystallographic and 17O NMR studies, as well as theoretical considerations, the origin of this uniqueness has been attributed to the through-space interaction between the bismuth centre and neighbouring oxygen atoms working favourably toward the stabilization of the bismuthonium intermediate.

The use of the 2-cyanoethyl group for carboxyl-protection is described. This group was readily introduced by esterification using ethylene cyanohydrin and the deprotection was carried out under mild conditions using tetrabutylammonium fluoride in dimethylformamide-tetrahydrofuran.

The first X-ray structure analysis of a bismuthio ylide has been made for 4,4-dimethyl-2,6-dioxo-1 -triphenylbismuthiocyclohexanide. The Bi–Cylide bond is 2.16 A, only 0.05–0.06 A shorter than the Bi–CPh single bond, revealing that the Bi–Cylide bond is polarized as C––Bi+ or O––CC–Bi+ with little double bond character between the Bi and the ylidic carbon.

Enamides and enimides were prepared stereospecifically from vinyl bromides by direct vinylic substitution in the presence of copper salt in aprotic polar solvents.

Carbanions derived from cyclic 1,3-dicarbonyl compounds reacted smoothly with some vinyl bromides and 1,3-enones in HMPA in the presence of copper(I) iodide to give geminally disubstituted alkanes in good yields. The products were easily dehydrated intramolecularly to form 4H-pyran derivatives almost quantitatively.

The Vilsmeier reaction of 3-nitropyrroles which are prepared by the reaction of nitroalkenes with the sodium salt of tosylmethylisocyanide gives 2-formyl-4-nitropyrroles in good yields.

Amides, thioamides, ureas, and thioureas were N-acetylated in good yield with acetic acid in the presence of methyl bis(1-naphthyl)bismuthinate at room temperature.

On heating with amines or alcohols in the presence of tris(2-methoxy phenyl)- or tris(2,6-dimethoxyphenyl)bismuthine, carboxylic acids bearing α-hydrogen are readily converted into the corresponding amides or esters in good yields while those without α-hydrogen remain intact.

3-Nitrochromenes bearing various substitutents have been prepared by the reaction of substituted salicylaldehydes with nitrostyrenes; some of these compounds have been found to display efficient optical second harmonic generation.

The use of the 2-cyanoethyl group for carboxyl-protection is described. This group was readily introduced by esterification using ethylene cyanohydrin and the deprotection was carried out under mild conditions using tetrabutylammonium fluoride in dimethylformamide-tetrahydrofuran.

Hantzsch cyclization of cyanoethyl 3-aminocrotonate and (E,Z)-4,4-dialkoxy-2-benzylideneacetoacetates 12a–h afforded the corresponding 3,4-trans-2-hydroxy-1,2,3,4-tetrahydropyridines 14a–h with high stereoselectivity. 1H NMR and X-ray analyses of compound 14a established the configuration of 3-H and 4-H as trans and that of 3-H and 2-OH as trans also.

Several 3-(2-cyanoethyl)-1, 4-dihydropyridine carboxylates (16) were prepared in moderate to good yields by means of the Hantzsch reaction. Treatment of these carboxylates with a weak base such as sodium sulfide or tetrabutylammonium fluoride at room temperature afforded smoothly the corresponding 1, 4-dihydropyridine monocarboxylic acids (18) in good yields. The monocarboxylic acids 18n and 18o were esterified with 2-nitrooxypropanol or N-(2-hydroxyethyl)nicotinamide p-toluenesulfonic acid salt to afford the selective coronary vasodilators CD-349 (5) and CD-832 (6), respectively.

In marked contrast to previously studied triarylbismuthanes, tris-(2,6-dimethoxyphenyl)bismuthane 1f showed itself to be a nucleophile strong enough to react with some activated alkyl halides via the probable formation of a bismuthonium intermediate. On the basis of X-ray crystallographic and 17O NMR studies, as well as theoretical considerations, the origin of this uniqueness has been attributed to the through-space interaction between the bismuth centre and neighbouring oxygen atoms working favourably toward the stabilization of the bismuthonium intermediate.

A general synthesis of 5-unsubstituted benzyl pyrrole-2-carboxylates was developed based on the reaction of β-nitroacetates with benzyl isocyanoacetate. The advantage of this route over other pyrrole syntheses was the regiochemical control of the substitution pattern on the pyrrole ring.

Tris(2-methoxyphenyl)bismuthane works as both a mild dehydrating agent and a good template for macrocyclic ester synthesis; prolonged heating of the bismuthane with a dicarboxylic acid anhydride and a glycol in toluene under reflux afforded the corresponding macrocyclic 1:1 diester in moderate to good yields, together with a small amount of a macrocyclic 2:2 tetraester.

Pyrroles fused with aromatic rings (isoindole derivatives) have been readily prepared by the reaction of aromatic nitro compounds with ethyl isocyanoacetate in the presence of DBU. The ease of this reaction depends on the aromaticity of the starting nitro aromatics. Polycyclic aromatic nitro compounds such as 1-nitroacenaphthylene or 9-nitrophenanthrene are more reactive than simple nitro aromatics such as nitrobenzene or nitronaphthalenes and give the corresponding pyrroles in good yields. Pyrroles prepared by this method have been converted into porphyrins fused with various aromatic rings by the reduction with LiAlH4 followed by treatment with an acid catalyst and oxidation with chloranil or oxygen. Tetra-1,2-naphthoporphyrin has been prepared by the reaction of 2-nitro-3,4-dihydronaphthalene or 1-nitronaphthalene with ethyl isocyanoacetate followed by reduction, tetramerization and oxidation. Thus, highly conjugated porphyrins are readily prepared starting from aromatic nitro compounds, and their electronic and optical properties can be controlled by choice of the starting aromatic nitro compound.

A new synthesis of push-pull dienes such as 4-nitro-1-phenylthiopenta-1,3-diene 4 and 1-dialkylamino-4-nitropenta-1,3-diene 5, is described. The X-ray crystal analysis shows that 4-nitro-1-(pyrrolidin-1-yl)penta-1,3-diene 5a is essentially planar in an E,E-configuration with r(C–C)= 1.42(1)A and r(CC)= 1.35(1) and 1.371(9)A. Compounds 5 showed a large solvatochromic effects similar to that of merocyanine dyes. Molecule 5a exhibits second harmonic generation (SHG) activity whose efficiency is 2.5 times that of urea (determined by a powder method at 1064 nm). For 5a, the molecular nonlinearity µβ is estimated to be 1200 × 10–48 esu which is calculated from the Pockel coefficient (r33) determined by electrooptic measurements of poled polymers of 5a in poly(methyl methacrylate) at 1300 nm. This value is relatively large for such small conjugated molecules, where donors and acceptors are bridged by only 4π electron systems.

3-Nitrochromenes are readily converted into 4-phosphorylchromenes on treatment with dialkyl phosphite in the presence of triethylamine in 60–70% yield. This method provides a general method for the preparation of alkenyl phosphonates from nitroalkenes and dialkyl phosphite.

New types of macrocyclic ligands with tetraoxa[n.n]metacyclophane molecular skeletons have been synthesized. The structures of 14,28-dibromo-1,8,15,22-tetraoxa[8.8]metacyclophane 2a, 16,32-dibromo-1,10,17,26-tetraoxa[10.10]metacyclophane 2b, 14,28-dibromo-2,7,16,21-tetraoxa[8.8]metacyclophane 3a, 16,32-dibromo-2,9,18,25-tetraoxa[10.10]metacyclophane 3c, 18,36-dibromo-2,11,20,29-tetraoxa[12.12]metacyclophane 3d, 20,40-dibromo-2,13,22,33-tetraoxa[14.14]metacyclophane 3e and 14,28-diiodo- 2,7,16,21-tetraoxa[8.8]metacyclophane 9a have been determined by single-crystal X-ray structure analyses. In compounds 2a and 2b, two bromide atoms face each other within the macrocyclic ring while in compounds 3c, 3d and 3e the bromine atoms face in opposite directions, outwards from the macrocyclic ring. In the smaller ring compounds 3a and 9a the structure was intermediate between these two types.Substitution of the bromine atoms via lithiation has been achieved smoothly with iodine and methyl iodide as the electrophiles to afford disubstituted compounds in good yields, while with trimethylsilyl chloride as the electrophile the mono-substituted compound has been obtained.

3,4-Diarylpyrroles (1) have been directly prepared in 20–50% yield by the reaction of β-nitrostyrenes with aqueous TiCl3 in 1,4-dioxane. Pyrroles 1 were also prepared via Barton–Zard pyrrole synthesis using the reaction of α-nitrostilbenes with ethyl isocyanoacetate followed by de-ethoxycarbonylation. 3,4-Diarylpyrroles have been converted into dodecaarylporphyrins by reaction with aromatic aldehydes. Various aryl groups are readily introduced at the periphery of porphyrins by this method. Phenyl substitution at any of the positions of pyrroles decreases Eox1/2, while E1/2red is almost unchanged. On the other hand, substitution of the 2-thienyl group affects both the HOMO and LUMO energies, and the UV-vis spectra of dodeca-2-thienylporphyrins (4f or 4i) are extremely red-shifted.

A series of vinylic and arylic phosphonates and phosphonic bis(diethylamides) were prepared by copper promoted substitution of the corresponding bromides. These π-electron conjugated phosphonates and phosphonic bis(diethylamides) were investigated to elucidate their optical and second harmonic generation (SHG) properties; it was found that diphenyl 2-(4-dimethylaminophenyl)ethenylphosphonate exhibited strong SHG activity, the efficiency being 13 times greater than that of urea.

Enamides and enimides were prepared stereospecifically from vinyl bromides by direct vinylic substitution in the presence of copper salt in aprotic polar solvents.