摘要:
An improved process for the metathesis of alkenyl esters utilizing substantially reduced catalyst levels is provided. For the process, an alkenyl ester of the formula ##STR1## where R is hydrogen or alkyl, R* is tertiary alkyl or an aromatic group, and n is an integer from 2 to 20 is reacted with a tungsten hexachloride/tetraalkyltin catalyst.
摘要:
Improved homogeneous metathesis catalysts are obtained by the use of a nitrogenous modifying agent with a tungsten compound and organotin compound. These modified catalyst systems used for olefin metathesis give significantly increased conversions and excellent product selectivity.
摘要:
This invention relates to carbodiimide compounds of the formula:Z--L--W--N.dbd.C.dbd.N--R.sub.1wherein Z is a signalling moiety or a protecting group; L is a divalent linking group; W is an alkylene group having up to 24 carbon atoms which can be substituted or interrupted by a water solubility enhancing group or cleavable S--S group; and R.sub.1 is an alkyl group having up to 18 carbon atoms. These compounds are useful in the nonradioactive labelling of nucleic acid probes, and methods employing same.
摘要翻译:本发明涉及下式的碳二亚胺化合物:Z-L-W-N = C = N-R1其中Z是信号传导部分或保护基; L是二价连接基团; W是具有至多24个碳原子的亚烷基,其可以被水溶性增强基团或可切割的S-S基团取代或中断; 并且R 1是具有至多18个碳原子的烷基。 这些化合物可用于核酸探针的非放射性标记和使用其的方法。
摘要:
A process is provided whereby the dimer fraction obtained from a boron trifluoride catalyzed oligomerization process is reacted with an .alpha.-olefin in the presence of a phosphoric acid-modified boron trifluoride catalyst to produce higher oligomeric products typically having viscosities (210.degree. F.) in the 4 to 8 centistoke range.
摘要:
This invention provides a process for preparing an oligomer of at least one polyunsaturated aliphatic C.sub.12-22 monocarboxylic acid ester in the presence of boron trifluoride resulting in a high yield or predominantly trimeric product which, upon hydrolysis, affords a high yield of polybasic, predominantly trimeric, acids. This invention further provides such a process with excellent recovery of the boron trifluoride.
摘要:
A process for recovering fatty materials, such as fatty acids and lower alkyl esters thereof, from supported nickel catalyst compositions is provided. For the process, the supported nickel catalyst composition, which may also contain non-nickel containing clays/earths, is extracted with a supercritical fluid, preferably supercritical carbon dioxide, to separate the fatty material from the supported nickel catalyst composition.
摘要:
Process for the preparation of terminally unsaturated alcohols by the thermal decomposition of a polycarbonate in the presence of titanium containing catalyst.
摘要:
Improved homogeneous metathesis catalysts are obtained by the use of a trivalent phosphorus modifying agent with a cocatalyst comprised of tungsten hexachloride and an organotin compound. These modified catalyst systems give significantly increased conversions and excellent product selectivity when used for olefin metathesis.