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A new family of second-generation light-driven molecular motors with different size substituents at the stereogenic center is presented. The experimental data demonstrate that an increase of the size of the substituent at the stereogenic center speeds up the rotary motion as the thermal helix inversion barrier is lowered.

The incomplete condensed monosilylated silesesquioxane were reacted with SiCi4 in the presence pf an amine, which yielded the dichloro compounds. These compounds could be hydrolyzed into the corresponding silesesquioxane containing geminal silanols and the acidities were compared with those of other silesesquioxane containing silanol groups.

Research has been conducted on the molecular motors. The synthesis and dynamic properties of these motors have been investigated and the results are reported.

Research was conducted to examine the crystal structure of the unsubstituted five-ring oligomer, p-bis(p-styrylstyryl)benzene or C38H30, designated (PPV). The similarity between the crystal structure of P5V4 found in the experiment and the generally accepted structural model for PPV makes it very desirable to analyze the optoelectronic characteristics of P5V4 in more detail. The approach will provide a better understanding of the transfer mechanisms for optical and charged excitations in semiconducting organic materials.

The synthesis and characterization of Fe(super II) and Fe(super III) complexes with the pentadentate ligand N4Py were described. These complexes were found to serve as precursors of a putative Fe(super III)-OOH species, obtained by addition of H2O2. The novel spectroscopic properties of this intermediate were then examined within the context of 'activated bleomycin,' the active form of the antitumor drug.

The dinuclear copper(II) complex (Cu2L(super 1){OAc}2)(ClO4) is synthesized by complexation of Cu(OAc)2.H2O with a new nonsymmetric dinucleating ligand, formed by condensation of pyridine and piperazin compounds. This dinuclear complex is formed via the initial formation of a mononuclear copper complex. The complexation behavior of nonsymmetric ligand is studied by microcalorimetric and UV spectroscopic measurements. These techniques establish the stepwise complexation behavior of the ligand.

A novel method is described to employ 1, 3-dimercaptoacetone as a synthon to add 2-propanone groups. The existing process reveals an equation with sulfide nucleophile and the leasing group. The new process reverses the locations of the two in association with that of the existing process. The absence of free 1,3-dimercaptoacetone is observed. Thioacetal is produced when a solution is used to instantly dimerize the molecule. The stereochemistry of the dimer and the path of the process are examined by 1H-NMR and 13C-NMR spectra. The carbonyl domain does not reveal any absorption.

Perylene (per) and ((n-C4H9)4N)(Co(mnt2)), where mnt is maleonitriledithiolate, were electrochemically oxidized to form individual crystals of (per4) (CO(mnt)2)3. X-ray diffraction was used at room temperature to determine the monoclinic composition, with a space group value having varying cell parameters. Trimers of perelyne units and (CO(mnt2)3) units were found in the structure with trimer possessing a perpendicular additional perylene molecule. A narrow and isotropic line was observed in the EPR spectrum at room temperature.

Preparation of neutral V(II) aryloxides can be done through ligand-replacement reactions on three V(II) complexes (Mz2V(Py)2)(mu-N2), Mz2V(py)2 and VCl2(TMEDA)2, where Mz = o-Me2NCH2C6H4, TMEDA = N,N,N',N'-tetramethylethylenediamine with several phenols or their corresponding alkali salts. It was possible to separate and characterize monomeric and neutral V(II) aryloxides with several coordination geometries.

Platinum and palladium complexes underwent insertion into the transannular S-S bonding of 1,5-diphosphadithiatetrazocines to form monomeric complexes having the formula M-(PPh2R')2(1,5-R4P2N4S2), wherein M represented either platinum or palladium. Nuclear magnetic resonance spectroscopy and X-ray analysis were conducted to characterize the structure and behavior of the complexes. The results showed that the complexes exhibited an n2-S,S' bonding mode.

Structural analysis of (perylene)Co-bis(maleonitriledithiolate)(CH2Cl2)0.5 crystals derived from the electrocrystallization of perylene and (n-C4H9)4N(Co mnt 2) revealed the presence of both molecular stacks and dimerized polymeric Co(mnt)2 chains in the crystal arrangement. This formation contributed to the high electrical conductivity of the compound. Moreover, electrical transport measurements at room temperature showed that electrical conductivity and absolute thermopower featured metallic properties at elevated temperatures.

An enantioselective route is described for three new second-generation light-driven molecular motors. These are the first molecular motors having a methoxy substituent at the stereogenic center and hence the photochemical and thermal isomerization steps involved in the rotary cycle of one of these new molecules are analyzed with various spectroscopic methods.

A series of molecular motors featuring a symmetrical acridane stator is described. Nanosecond transient absorption spectroscopy has allowed for the thermal process to be followed accurately at ambient temperature and the rotary motor has operated at 0.5 MHz rotational frequencies under optimal conditions.