Expertise in Chemical
Reactions
Grignard Reaction
Specific technology has been developed to synthesize Grignard
reagent by in situ activation of magnesium. With the activated
magnesium, Grignard reagent can be formed at low temperatures.
Facilities are there to generate Grignard reagent in refluxing
too. Non-aqueous cooling medium is used in the condenser for safety
reasons.
Friedel-Craft Reaction
Facilities are adequate for in situ generation of the acid chloride
required for Friedel-Craft Reaction. HPLC method is developed
to monitor in situ formation of acid chloride through derivatisation
since acid chloride is not stable under reverse phase HPLC conditions.
Catalytic Hydrogenation
Hydrogenator of 2000 ltrs capacity is available for hydrogenation.
Pyrophoric palladium carbon is handled in a safe manner. Reductive
amination coupled with debenzylation is carried out in one-pot
reaction. Differences in situ generated intermediates are monitored
by GC. and Cyanogroup of a highly substituted ester derivative
is reduced to a primary amino group in the presence of Raney nickel
at a pressure of 6-8 Kg/cm2
Cyanation
Cyanations are carried out in homogeneous and biphasic media.
A proper method of effluent treatment has been developed for destruction
of residual cyanides.
Bromination
Bromination of the active methylene group is a tricky reaction
as there is a possibility of formation of dibromo derivatives.Suitable
reaction condition at commercial scale have been developed for
the optimum formation of the desired product.
Wolff-Kishner Reduction
Ketone of one of the intermediates is reduced using hydrazine
hydrate and sodium hydroxide.Appropriate temperature condition
have been established at commercial scale to get optimum yield
of the product.
Michael Reaction
Dialkylation of primary amine is carried out with ethyl acrylate
and the Resulting dialkylated product is used in subsequent step
without purification. Excellent technology has been stabilized
on commercial scale to obtain quality dialkylamine without purification
under Michael reaction.Similarly technology for synthesizing highly
substituted 1,4-diketones involving the Michael addition of aromatic
aldehydes to activated olefins under the Steller catalytic condition
have been successfully scaled up.
Carbon Homologation
Low temperature experimental conditions involving coupling of
n-butyl lithium/diisopropylamine generated carbanion derived from
esters with hydroxy substituted esters leading to ß-ketoester
via a 2-carbon homologation have been scaled up.A similar transformation
involving the reaction of a dianion generated from a ß-ketoester
(in the presence of sodium hydride/n-butyllithium at low temperatures)
with an aldehyde provides advanced pharmaceutical intermediate
via a 4-carbon homologation methodology.
Intermolecular Cyclization
Acid assisted experimental conditions have been developed for
the cyclization of tetrasubstituted 1,4-diketones with a highly
functionalized primary amine in a ternary solvent system to provide
an advance pyrrole derivative in a reasonably good yield.
Intramolecular Cyclization
A highly concentrated solution of an N-alkylated aromatic ketone
derivative is forced to undergo intramolecular cyclisation in
the presence of a transition metal salt to yield an indole derivative.
Ketalisation
Acid catalysed ketalisation of a highly sensitive 1,3-diol ester
under very mild experimental conditions provides a very pure crystalline
intermediate.
Deketalisation
Under extremely controlled and mild acidic conditions,
protected ketal functionality of a highly sensitive substituted
heterocyclic compound is selectively deprotected in the presence
of tertiary butyl ester group to provide an advanced intermediate.
Condensation
A high yield synthesis of an activated trisubstituted olefin via
condensation of a ß-ketoester derivative and aromatic aldehydes
has been standardized under very mild conditions.

Amide Formation
Substituted ß-ketoester is reacted with aromatic amines
under refluxing conditions to provide the amide derivative in
high purity which is then straightway used in the next stage without
further purification.
Methylation
Process for methylation using dimethylsulfate as a reagent has
been commercialized incorporating all safety aspects.
Hydrolysis
Nitrile of one of the intermediate is hydrolysed to carboxylic
acid giving almost quantitative yield at the commercial scale.
In another intermediate ester is hydrolysed to give carboxylic
acid.
Esterification
Conditions for esterification have been developed on commercial
scale using different acids to give high purity product minimizing
effluent and pollution load.
Reduction
Ester of one of the intermediate is reduced to alcohol using sodium
borohydride activated with aluminium chloride. Process for ketone
reduction to form a hydroxy group has been commercialized using
sodium borohydride.
Stereoselective
Reduction
Very low temperature experimental conditions (-90ºC to 100ºC)
have been utilized to carry out stereoselective reduction of hydroxy
substituted ß-ketoester in the presence of boranes and sodium
borohydride to synthesize cis 1,3-diol derivatives. Higher temperatures
lead to the formation of trans 1,3 diols in higher proportions
which cannot be easily separated from the cis diol derivatives.
Morepen’s Strengths
- Chemistry
Chiral
Synthesis • Montelukast Sodium
• Moxifloxacin Grignard reaction
• Loratadine • Montelukast •
Fexofenadine Hydrochloride Fridel Craft
reaction • Loratadine •
Fluvastatin Sodium • Fexofenadine Hydrochloride
High pressure Hydrogenation •
Atorvastatin Calcium • Pioglitazone Hydrochloride
• Moxifloxacin Hydrochloride Low temperature
stereo specific reduction • Atorvastatin
Calcium • Fluvastatin Sodium 2
& 3 Carbon Homologation reactions
• Atorvastatin Calcium • Fluvastatin
Sodium |
Cyanation
• Loratadine Merwein Arylation
• Pioglitazone Hydrochloride Bromination
• Sultamicillin Tosylate • Zafirlukast
• Montelukast Sodium • Cisapride
Alkylation • Montelukast
Sodium • Fexofenadine Hydrochloride •
Cisapride Hetero Cyclization
• Atorvastatin Calcium • Pioglitazone
Hydrochloride • Fluvastatin Sodium •
Paroxetine Hydrochloride Vilsmair Haack
reaction
• Fluvastatin Sodium
Nucleophilic substitution • Montelukast
Sodium • Gatifloxacin Hydrochloride |
|