Disclosed is a preparation method for an SGLT2 inhibitor intermediate V, the method comprising: adding a compound IV to a solvent, and in the presence of a catalytic reagent, carrying out heat preservation reaction with a fluorination reagent. The preparation process for the intermediate V is simple in operations, mild in reaction conditions and high in safety, facilitates quality control and is suitable for industrial production. In addition, the intermediate V prepared by the method is high in purity, has few side reaction product monofluoro-impurity shown as structural Formula V, is easy to purify, and is applicable to quality research on active pharmaceutical ingredients and preparations of the SGLT2 inhibitor.

The present invention relates to a process of the asymmetric hydrogenation of a ketal of an unsaturated ketone or an acetal of an unsaturated aldehyde by molecular hydrogen in the presence of at least one chiral iridium complex. This process yields chiral compounds in a very efficient way and is very advantageous in that the amount of iridium complex can be remarkably reduced.

The present invention relates to a process of the asymmetric hydrogenation of a ketal of an unsaturated ketone or an acetal of an unsaturated aldehyde by molecular hydrogen in the presence of at least one chiral iridium complex. This process yields chiral compounds in a very efficient way and is very advantageous in that the amount of iridium complex can be remarkably reduced.

The present invention relates to a process of the asymmetric hydrogenation of a ketal of an unsaturated ketone or an acetal of an unsaturated aldehyde by molecular hydrogen in the presence of at least one chiral iridium complex. This process yields chiral compounds in a very efficient way and is very advantageous in that the amount of iridium complex can be remarkably reduced.

Disclosed herein is a process for preparing a compound of formula (I) starting from a compound of formula (II). Also disclosed herein are a process to prepare a compound of formula (II) and the compound of formula (II).

Disclosed herein is a process for preparing a compound of formula (I) starting from a compound of formula (II). Also disclosed herein are a process to prepare a compound of formula (II) and the compound of formula (II).

The disclosure discloses a method for an addition reaction of acetylene and a ketone compound. The method includes the following steps: S1, providing a continuous reaction device, wherein the continuous reaction device includes a plurality of bubble tubular reactors being connected with each other through connecting tubes; feeding a raw material solution containing the ketone compound and alkali into the plurality of bubble tubular reactors, and S3, under normal pressure, pumping acetylene from the bottom of the first bubble tubular reactor for the addition reaction. By applying the technical solution of the invention, acetylene reacts with the ketone compound in the plurality of bubble tubular reactors arranged in series, which can ensure the sufficient gas-liquid contact time, and thus making full use of the acetylene gas, improving the utilization rate thereof, effectively reduing the amount of acetylene, reducing costs, and further improving the safety.

The disclosure discloses a method for an addition reaction of acetylene and a ketone compound. The method includes the following steps: S1, providing a continuous reaction device, wherein the continuous reaction device includes a plurality of bubble tubular reactors being connected with each other through connecting tubes; feeding a raw material solution containing the ketone compound and alkali into the plurality of bubble tubular reactors, and S3, under normal pressure, pumping acetylene from the bottom of the first bubble tubular reactor for the addition reaction. By applying the technical solution of the invention, acetylene reacts with the ketone compound in the plurality of bubble tubular reactors arranged in series, which can ensure the sufficient gas-liquid contact time, and thus making full use of the acetylene gas, improving the utilization rate thereof, effectively reduing the amount of acetylene, reducing costs, and further improving the safety.

The disclosure discloses a method for an addition reaction of acetylene and a ketone compound. The method includes the following steps: S1, providing a continuous reaction device, wherein the continuous reaction device includes a plurality of bubble tubular reactors being connected with each other through connecting tubes; feeding a raw material solution containing the ketone compound and alkali into the plurality of bubble tubular reactors, and S3, under normal pressure, pumping acetylene from the bottom of the first bubble tubular reactor for the addition reaction. By applying the technical solution of the invention, acetylene reacts with the ketone compound in the plurality of bubble tubular reactors arranged in series, which can ensure the sufficient gas-liquid contact time, and thus making full use of the acetylene gas, improving the utilization rate thereof, effectively reduing the amount of acetylene, reducing costs, and further improving the safety.

The present invention provides 5-(2-butyl-1,3-dioxolan-2-yl)-1-methylpentyl acetate of the following formula (1).

The present invention further provides the aforesaid 5-(2-butyl-1,3-dioxolan-2-yl)-1-methylpentyl acetate (1), the process comprising the step of subjecting an organic magnesium compound (2) of the following general formula (2), wherein X.sup.1 represents a halogen atom or a 3-(2-butyl-1,3-dioxolan-2-yl) propyl group, to a nucleophilic addition reaction with propylene oxide of the following formula (3) and then reacting with an acetylating agent of the following general formula (4), wherein X.sup.2 represents a halogen atom, an acetoxy group, a methoxy group, or an ethoxy group, to form 5-(2-butyl-1,3-dioxolan-2-yl)-1-methylpentyl acetate (1).

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