摘要:
A process for preparing venlafaxine in a high yield as well as processes for producing venlafaxine hydrochloride of form I having a very high polymorphic purity are described.
摘要:
4-Acetoxystyrene is reacted with a base in a solvent to form a salt of 4-hydroxystyrene via saponification. Alternatively, 4-hydroxystyrene is reacted with a base to form a salt of 4-hydroxystyrene. In the latter case, the 4-hydroxystyrene is prepared by the transesterification of 4-acetoxystyrene. Subsequently or simultaneously, the salt of 4-hydroxystyrene is reacted, preferably in situ, with di-tertiary-butyl-dicarbonate to form 4-tertiarybutoxycarbonyloxystyrene.
摘要:
4-Acetoxystyrene is reacted with a base in a solvent to form a salt of 4-hydroxystyrene via saponification. Alternatively, 4-hydroxystyrene is reacted with a base to form a salt of 4-hydroxystyrene. In the latter case, the 4-hydroxystyrene is prepared by the transesterification of 4-acetoxystyrene. Subsequently or simultaneously, the salt of 4-hydroxystyrene is reacted, preferably in situ. with di-tertiary-butyl-dicarbonate to form 4-tertiary-butoxycarbonyloxystyrene.
摘要:
The present invention pertains to a method of forming a salt of 4-hydroxystyrene by reacting 4-acetoxystyrene with a suitable base in a suitable solvent system. Subsequently, or simultaneously, the salt of 4-hydroxystyrene can be reacted, preferably in situ, with di-tertiary-butyl-dicarbonate to form 4-tertiary-butoxycarbonyloxystyrene.
摘要:
A process for preparing an olefin polymerization catalyst which comprises halogenating a magnesium-di-(3-halo- or 3- C.sub.1 to C.sub.8 alkoxy-phenoxide) with a halide of tetravalent titanium in the presence of a halohydrocarbon, recovering the solid reaction product from the reaction mixture and combining the solid reaction product with an organo aluminium compound and an electron donor.
摘要:
Hydrocarbon-soluble complexes of magnesium alkoxides with magnesium aryl oxides are described. The magnesium aryl oxide moiety is derived from a hindered aromatic alcohol. The complexes can be formed by reaction between a magnesium alkyl and a mixture of aliphatic alcohols and a hindered aromatic alcohol.
摘要:
This invention comprises an alkylation, reduction and transesterification process for the preparation of ester substituted phenols. The products are useful as antioxidants and may be prepared in high yields and with a high degree of purity.
摘要:
Heating 3,3'',5,5''-tetraphenyldiphenoquinone above its melting point but below its carbonization temperature causes an intramolecular disproportionation reaction the progress of which is monitored by the color change. Three sexiphenyl compounds are produced which are separable by chromatography. Two of the products are new compounds, having one and two dibenzofuran groups, respectively in their structures. The bidibenzofuran compound can be converted to 5'',5''''-diphenyl-m-quaterphenyl2,2''''''-diol, useful in the preparation of polycarbonates and polyester. The other two products can be reworked to serve as a recycle feedstock.