One of the most common methods to determine the extent of double-bond conversion is Fouriertransform infrared spectroscopy (FTIR), (2,11) which can detect the stretching vibrations of carbon-carbon double bonds
involved in polymerization.
"Carbon-carbon double bonds
show up everywhere," Grubbs notes, adding that this ubiquity "allows these catalysts to be plugged into many different reactions."
exp.) featured resonances corresponding to two methyl groups (identical to those at the terminal of fatty acid chain) resonating at dH/ dC 0.88 (6H, t, J= 7.2 Hz)/ 14.2, two hetero linked methine functions resonating at dH/dC 4.32 (1H, br s)/ 74.6 and 3.92 (1H, m)/ 54.4, a hetero linked methylene group resonating at dH/dC 3.71 (1H, dd, J= 10.8, 3.6 Hz) and 3.95 (1H, dd, J= 11.4, 3.6 Hz)/ 62.4, two disubstituted carbon-carbon double bonds
resonating at dH/dC 4.55 (1H, dt, J= 15.0, 6.0 Hz)/ 128.9, 5.78 (1H, dt, J= 15.0, 6.6 Hz)/ 131.4, 5.37 (1H, dt, J= 15.0, 6.6 Hz)/ 134.3, and 5.42 (1H, dt, J= 15.0, 6.6 Hz)/ 129.1 and a large number of methylene protons resonating at dH 1.25 (Characteristic of long chain aliphatic fatty methylenes).
PMMA and MAPTMS present absorptions at 1638 [cm.sup.-1] due to vinylic carbon-carbon double bonds
. In the acrylate, these groups arise from the residual monomer.
With the availability of a large number of unsaturated polymers of differing microstructures, the selective reduction of carbon-carbon double bonds
offers a way of producing a wide variety of specialty polymers.
The a, b-unsaturated esters were converted to the corresponding alcohols using diisobutylaluminium hydride (DIBAL) in order to determine the stereochemistry of the carbon-carbon double bonds
(C=C) in a, b-unsaturated esters.
VTMS contains functional group of both carbon-carbon double bonds
Highly versatile molecules that contain carbon-carbon double bonds
, alkenes, or olefins, are ubiquitous in medicinally relevant and biologically active molecules.
Following an introduction to nomenclature and general mechanisms, chapters discuss mechanisms of CTI around the carbon-carbon double bonds
via the triplet state; retinal binding proteins; non-retinal chromophoric proteins; fatty acids and phospholipids; in silico dynamic studies in organic and biological systems; chemical aspects of the restricted rotation of esters, amides, and related compounds; amide CTI in peptides and proteins; enzymes catalyzing peptide bond CTI; tailoring amides; peptidyl prolyl isomerases as new targets for novel therapeutics; and metal complexes.
With that inspiration, Gates focused on substituting one of butyl rubber's carbon-carbon double bonds
with a phosphorus-carbon double bond.