Conjugated organic materials offer exciting possibilities in science andtechnology. Through chemical doping with an external substrate they can exhibit very
good conducting properties on par with metals and at the same time can possess the
flexibility of plastics. The polymer, poly-phenylenevinylene (PPV) is a well known
conjugated organic material. Polymers and small conjugated organic materials
resembling such PPV’s are known for their promise in electrooptical devices and as light
emitting materials. Mostly, these are the compounds with alternating carbon-carbon (pπ-pπ) double bonds in a conjugated aromatic network. The properties of these materials can
be tuned by molecular changes through chemical synthesis.
This study details the synthesis and characterization of such small conjugated
organophosphorus compounds having phosphorus-carbon double bonds in conjugated
carbon network. The initial study is focused on synthesis and detailed investigation on the
structural and photochemical properties of meta-terphenyl phosphaalkenes (X-Dmp-
P=C(H)-Ph-X’, Dmp: 2,6-dimesitylphenyl). Through these studies, it was observed that
these meta-terphenyl phosphaalkenes are photochemically active unlike related metaterphenyl
diphosphene (Dmp-P=P-Dmp), but similar to Mes* diphosphene (Mes*-P=PMes*,
Mes*: 2,4,6-tri-tert-butylphenyl) and phosphaalkene (Mes*-P=C(H)-Ph). In
chapter 3, a detailed investigation on the synthesis and studies related to the effect of
different electron donating and accepting groups on the meta-terphenyl phosphaalkenes
(X-Dmp-P=C(H)-Ph-X’, X: H, MeO, Me2N; X’: H, CN, NO2) were discussed. The
chapter 4, details the synthesis and studies related to new molecules of the type “2,6-
diaryl-benzo-bisoxaphosphole” were reported. These new compounds found to be
relatively more stable than the synthesized meta-terphenyl phosphaalkenes. The complete
synthesis and characterization of these compounds were discussed.