This thesis presents basic studies, including structural, optical and transport measurements, on novel chalcogenide powders and single crystals. BiCuOSe crystals have been synthesized for the first time. The crystal structure of BiCuOSe has been refined and the optical band gap has been measured to be 0.83eV. Crystal structure refinements of...
The thermolysis of trans-1 -trimethylsiloxy- 1-vinylcyclotridec-
3-ene (VI-OTMS) led to the formation of two major products: 4-vinylcyclotridecanone
(VII) and cyclopentadec-5-en-l-one (VIII) after
hydrolysis. Ketone VII is produced by a concerted [3, 3] sigmatropic
shift, while ketone VIII is formed by a [1, 3] sigmatropic shift with
a concerted or diradical...
The potassium salts of a series of 1-vinylcycloalk-3-en-l-ols were found to undergo ring expanding [1, 3]-sigmatropic shifts at 25° when dissolved in hexamethylphosphoramide (HMPA) or 1, 2-dimethoxyethane (DME) with 18-crown-6. The yields and reaction rates were compared with those of the corresponding Siloxy-Cope ring expansions. These anionic cases showed about...
Both oxy-Cope and siloxy-Cope rearrangements involve
(1, 3) and (3, 3) sigrnatropic shifts. Both the concerted mechanism,
and the stepwise mechanism via a diradical intermediate are possible.
In a cyclic system such as cis-l-vinylcyclooct-3-en-l-ol, the thermal
rearrangement takes place preferably through a diradical intermediate.
At high temperature, the reaction also...
The (±) 8,9:13,14-diseco-norestradiol, a large ring hormone
analog, and its related derivatives, were prepared by a ring expansion
approach. The key step of this approach is the establishment of the
benzocyclododecenone system via the Caubere reaction. This step
not only provides a favorable ring size, it also sets the necessary...
The thermal and anionic rearrangements of substituted 1-vinyltrans-
cyclotridec-3-en-l-ol compounds have been studied to determine
what effects substituents would have on the sigmatropic shift when
placed on the two positions of the 1-vinyl group.
For the thermal rearrangements, the a-substituted vinyl-trans-cyclotridecenols
gave both the [3,3] and [1,3] shift products of...
The reaction of cyclodeca-1,215triene with mercuric salts
gave only rearranged hydrocarbon, tricyclo[4.4.0.0²'⁴]deca-5ene
in acetic acid. Other catalysts [Rh(CO)₂C1]₂ and AgC10₄ gave
the same rearranged hydrocarbon. The isomerization is proposed
to proceed through a "metalcomplexed" carbenoid intermediate.
The reaction of bicyclo[7.1.0 ]deca-213diene gave
oxymercurated products.
Part 1
The pyrolysis of cis-1-trimethylsiloxy-1-cyclopr opyl-3-cyclononene in the temperature range 285-350° is described. Instead
of siloxy-Cope rearrangement, undesired desiloxylation took place.
Part 2
Gas-phase pyrolytic rearrangement of 2-phenyl-1-trimethylsiloxy-1-vinylcyclononane was investigated in a static system
in the temperature range 213-330°. It was discovered that
three major products resulted: cis- and...