Abstract:
A process for producing a compound of formula (I) is provided. The process comprises reacting a mixture comprising a compound of formula (IIA) and a compound of formula (IIB) with an alkyl alcohol in the presence of a Candida antarctica lipase B enzyme to produce a product comprising the compound of formula (I) and the compound of formula (IIB); wherein R 1 is C 1 to C 6 alkyl; and wherein R 2 is H or C 1 to C 12 alkyl. Also provided are processes for the production of R-lactic acid, oligomeric R-lactic acid, R,R-lactide, poly-R-lactic acid, alkyl S-lactate, S-lactic acid, oligomeric S-lactic acid, S,S-lactide, poly S-lactic acid and stereocomplex polylactic acid.
Abstract:
The invention relates to a process for the manufacture of an alkylfluoroacrylate starting from alkylfluoroacetate and an oxalic acid ester, wherein an alkane liquid under the reaction conditions is applied as the solvent in one of the reaction steps.
Abstract:
Beschrieben wird ein neues Verfahren zur Herstellung von α-halogensubstituierten Carbonsäureestern, beispielsweise von HCF 2 (C(O)OR. Dabei werden entsprechende Malonsäurediester mit einer Carbonsäure, beispielsweise Trifluoressigsäure, in Anwesenheit eines Katalysators, insbesondere eines "Onium"-Salzes einer Carbonsäure oder einer effektiven Menge einer Protonen freisetzenden Säure, vorzugsweise einer Sulfonsäure wie Alkyl- oder Arylsulfonsäuren, oder einer Mineralsäure umgeestert und decarboxyliert. Das Verfahren wird zweckmässig wasserfrei durchgeführt. Vorteil des Verfahrens ist die einfache Durchführung. Die Anwesenheit eines zusätzlichen Katalysators, wie eines Übergangsmetallsalzes, kann vorteilhaft sein.
Abstract:
A process for producing a fluorinated vinyl ether through a simple procedure in high yield from a fluorinated acid fluoride compound having an ester group, which is a precursor for a carboxy group, or an SO 2 F group, which is a precursor for a sulfo group. The process comprises thermally decomposing a carboxylic acid potassium salt having a specific structure represented by the following formula in the absence of a solvent and/or while keeping the salt in a solid state. (1) (In the formula, X is −CO 2 R or −SO 2 F and R is alkyl.)
Abstract translation:一种由具有酯基的氟化酸氟化合物(其为羧基的前体)或SO 2 F F基团通过简单的方法从高产率制备氟代乙烯基醚的方法,其中 是磺基的前体。 该方法包括在不存在溶剂的情况下和/或在保持盐处于固态的同时热分解具有由下式表示的特定结构的羧酸钾盐。 (1)(式中,X为-CO 2 S,R 2,-SO 2 S 2 F,R为烷基。
Abstract:
The present invention provides improved process for preparation of Molnupiravir compound of formula (I) having high purity and yield by avoiding excess use of organic solvent & tedious column chromatography purification. further present invention provides improved process for preparation of compound of formula (V) in single step reaction having high yield and high purity.
Abstract:
The current invention relates to a process for the production of 1,2-alkanediols comprising the steps of: providing a dialkyl oxalate (component A); providing an ester or an aldehyde (component B), which is characterised by having at least one hydrogen atom bound to the second (alpha-)carbon atom; reaction of the dialkyl oxalate (component A) with an ester or aldehyde (component B) in the presence of a base (component C), thereby forming at least one new carbon-carbon bond and obtaining an intermediate; conversion of the obtained intermediate to an alpha-keto carboxylic acid, an alpha-keto ester or a mixture thereof; optionally, esterification of the obtained alpha-keto carboxylic acid; reduction of the alpha-keto carboxylic acid or its ester to the corresponding 1,2-alkanediol; and optionally, purification of the obtained 1,2-alkanediol and/or any of the intermediates formed during the prior steps.
Abstract:
The invention discloses a method for the preparation of tert-butyl 6-chloro-3,5- dioxohexanoatefrom Meldrum's acid derivative and its use for the preparation of tert-butyl (4R,6S)-(6-hydroxymethyl-2,2-dimethyl-1,3-dioxan-4-yl)acetate(BHA), Rosuvastatin and Atorvastatin.
Abstract:
Procédé de préparation des composés de formule (IV) dans laquelle R 1 , R 2 , R 3 et R 4 , identiques ou différents, représentent chacun un atome d'hydrogène, un groupement alkyle (C 1 -C 6 ) linéaire ou ramifié, un groupement alkoxy (C 1 -C 6 ) linéaire ou ramifié, un atome de fluor, de chlore, un groupement aminé protégé, un groupement hydroxyle protégé, un groupement alkoxycarbonyle dans lequel le groupement alkoxy est (C 1 -C 6 ) linéaire ou ramifié, un groupement CF 3 , ou R 1 =R 4 =H et R 2 et R 3 forment ensemble avec les atomes de carbone qui les portent un groupement 1,3-dioxolane, R 5 représente un groupement alkyle (C 1 -C 6 ) linéaire ou ramifié, saturé ou insaturé, un groupement hydroxyalkyle (C 1 -C 6 ) linéaire ou ramifié dont la fonction hydroxyle est protégée, ou un groupement CO 2 R 7 dans lequel R 7 est un groupement alkyle (C 1 -C 6 ) linéaire ou ramifié, R 6 représente un groupement cyano ou un groupement CO 2 R 8 dans lequel R 8 est un groupement alkyle (C 1 -C 6 ) linéaire ou ramifié. Application à la synthèse de l'ivabradine, de ses sels d'addition à un acide pharmaceutiquement acceptable et de leurs hydrates.