The present disclosure relates to the field of drug synthesis, and discloses a method for the preparation of trans-N-benzyloxycarbonyl-(3-hydroxy-2-piperidinyl)-2-propanone as an intermediate of halofuginone. In the preparation method according to the present disclosure, for the first time, trans-N-benzyloxycarbonyl-(3-hydroxy-2-piperidinyl)-2-propanone as shown in Formula I is obtained from amino-substituted pentanal and a thiazolyl sulfoxide compound as raw materials by Mislow-Evans rearrangement reaction and subsequent Lewis acid catalysis. The method for the preparation of trans-N-benzyloxycarbonyl-(3-hydroxy-2-piperidinyl)-2-propanone as an intermediate of halofuginone according to the present disclosure has high yields and stable qualities, provides a new reference route for the synthesis of trans-N-benzyloxycarbonyl-(3-hydroxy-2-piperidinyl)-2-propanone, avoids the reduction of pyridine, and overcomes the disadvantage of requiring the use of an expensive metal catalyst Rh/A1203.

The present disclosure relates to the field of drug synthesis, and discloses a method for the preparation of trans-N-benzyloxycarbonyl-(3-hydroxy-2-piperidinyl)-2-propanone as an intermediate of halofuginone. In the preparation method according to the present disclosure, for the first time, trans-N-benzyloxycarbonyl-(3-hydroxy-2-piperidinyl)-2-propanone as shown in Formula I is obtained from amino-substituted pentanal and a thiazolyl sulfoxide compound as raw materials by Mislow-Evans rearrangement reaction and subsequent Lewis acid catalysis. The method for the preparation of trans-N-benzyloxycarbonyl-(3-hydroxy-2-piperidinyl)-2-propanone as an intermediate of halofuginone according to the present disclosure has high yields and stable qualities, provides a new reference route for the synthesis of trans-N-benzyloxycarbonyl-(3-hydroxy-2-piperidinyl)-2-propanone, avoids the reduction of pyridine, and overcomes the disadvantage of requiring the use of an expensive metal catalyst Rh/A1203.

The present invention relates to kinetic resolution of racemic δ-hydroxyl ester via asymmetric catalytic hydrogenation and an application thereof. In the presence of chiral spiro pyridyl phosphine ligand Iridium catalyst and base, racemic δ-hydroxyl esters were subjected to asymmetric catalytic hydrogenation to obtain extent optical purity chiral δ-hydroxyl esters and corresponding 1,5-diols. The method is a new, efficient, highly selective, economical, desirably operable and environmentally friendly method suitable for industrial production. An optically active chiral δ-hydroxyl ester and 1,5-diols can be obtained at very high enantioselectivity and yield with relatively low usage of catalyst. The chiral δ-hydroxyl ester and 1,5-diols obtained by using the method can be used as a critical raw material for asymmetric synthesis of chiral drugs (R)-lisofylline and natural drugs (+)-civet, (−)-indolizidine 167B and (−)-coniine.

The present invention relates to kinetic resolution of racemic δ-hydroxyl ester via asymmetric catalytic hydrogenation and an application thereof. In the presence of chiral spiro pyridyl phosphine ligand Iridium catalyst and base, racemic δ-hydroxyl esters were subjected to asymmetric catalytic hydrogenation to obtain extent optical purity chiral δ-hydroxyl esters and corresponding 1,5-diols. The method is a new, efficient, highly selective, economical, desirably operable and environmentally friendly method suitable for industrial production. An optically active chiral δ-hydroxyl ester and 1,5-diols can be obtained at very high enantioselectivity and yield with relatively low usage of catalyst. The chiral δ-hydroxyl ester and 1,5-diols obtained by using the method can be used as a critical raw material for asymmetric synthesis of chiral drugs (R)-lisofylline and natural drugs (+)-civet, (−)-indolizidine 167B and (−)-coniine.

The present disclosure is related to an improved and efficient process for preparation of (3R,4R)-(1-benzyl-4-methylpiperidin-3-yl)-methylamine which comprises:

(a) N-acylation of 3-Amino-4-methyl pyridine; (b) Quarternization of 3-Acetylamino-4-methyl pyridine using benzyl halide; (c) Partial reduction of quarternized 3-Acetylamino-4-methyl pyridine by Sodium borohydride in Methanol or water; (d) Hydrolysis of partially reduced product to 1-Benzyl-4-methylpiperidin-3-one in presence of acid; (e) Reductive amination of 1-Benzyl-4-methylpiperidin-3-one using Methanolic methylamine in presence of Titanium(IV) isopropoxide in Methanol; (f) Resolution of 1-Benzyl-4-methylpiperidin-3-yl)-methylamine using Ditoluoyl (L) tartaric acid to get (3R,4R)-(1-benzyl-4-methylpiperidin-3-yl)-methylamine. The disclosure is also related to novel intermediates:

##STR00001##

wherein R, R′ and X are as described in the specification.

A novel process is provided for the efficient preparation of an asymmetric compound of structural formula I: ##STR00001##
employing dynamic kinetic resolution (DKR). The DKR process involves an enzymatic enantioselective amination reaction catalyzed by transaminases. The process can be used to manufacture key intermediates in the preparation of poly (ADP-ribose) polymerase (PARP) inhibitors which may be useful for the treatment of cancer.

A novel process is provided for the efficient preparation of an asymmetric compound of structural formula I: ##STR00001##
employing dynamic kinetic resolution (DKR). The DKR process involves an enzymatic enantioselective amination reaction catalyzed by transaminases. The process can be used to manufacture key intermediates in the preparation of poly (ADP-ribose) polymerase (PARP) inhibitors which may be useful for the treatment of cancer.

Disclosed is a process for the preparation of certain intermediates, e.g. process for preparing a compound of formula (I) or a pharmaceutically acceptable salt thereof, in an enantioenriched form, which intermediate and processes are useful in the preparation of a BTK inhibitor, such as ibrutinib.

##STR00001##

The invention relates to tungsten imido alkylidene compounds bearing a ligand derived from a 1,1′-binaphthyl-2-ol or a 5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl-2-ol which bind to tungsten in its olate-form via proton abstraction from the phenolic OH group. The complexes may be used in various olefinic metathesis reactions, preferably ethenolysis and cross-metathesis of unsaturated fatty acid esters, and ring-closing metathesis reactions.

The invention relates to tungsten imido alkylidene compounds bearing a ligand derived from a 1,1′-binaphthyl-2-ol or a 5,5′,6,6′,7,7′,8,8′-octahydro-1,1′-binaphthyl-2-ol which bind to tungsten in its olate-form via proton abstraction from the phenolic OH group. The complexes may be used in various olefinic metathesis reactions, preferably ethenolysis and cross-metathesis of unsaturated fatty acid esters, and ring-closing metathesis reactions.