Method for preparing lactames, comprising a photonitrosation step, followed by a beckmann transposition step

Abstract

The invention relates to a method for preparing lactames, according to which a photonitrosation of a cycloallcane is carried out using nitrosyl chloride (NOCI). According to the invention, said photonitrosation is carried out by means of LEDs emitting a monochromatic light. The method according to the invention can also include a step comprising Beckmann transposition/dechlorination of the oxime hydrochloride generated during said phonitrosation, preferably carried out in a glass microreactor.

1 . A process for preparing lactames, comprising the step of a photonitrosation of a cycloalkane using nitrosyl chloride (NOCl), wherein said photonitrosation is carried out by means of LEDs emitting a monochromatic light. 
     
     
         2 . The process as claimed in  claim 1 , in which said cycloalkane is cyclododecane. 
     
     
         3 . The process as claimed in  claim 1 , wherein the monochromatic light emitted by the LEDs has an average wavelength value between 550 to 650 nm. 
     
     
         4 . The process as claimed in  claim 3 , wherein the monochromatic light emitted by the LEDs has an average wavelength value of from 585 to 595 nm. 
     
     
         5 . The process as claimed in  claim 1 , wherein a microreactor is used to carry out the photonitrosation of the cycloalkane. 
     
     
         6 . The process as claimed in  claim 5 , wherein the body of the microreactor is made of glass. 
     
     
         7 . The process as claimed in  claim 1 , wherein said process further comprises a step of Beckmann rearrangement/dechlorination of the oxime hydrochloride generated during said photonitrosation, wherein a microreactor is used to carry out the Beckmann rearrangement/dechlorination step. 
     
     
         8 . The process as claimed in  claim 7 , wherein the body of the microreactor used for said Beckmann rearrangement/dechlorination of the oxime hydrochloride comprises tantalum, a fluoropolymer, a glass steel or glass. 
     
     
         9 . (canceled) 
     
     
         10 . The process as claimed in  claim 9 , in which the cycloalkane is cyclododecane. 
     
     
         11 . The process as claimed in  claim 8 , wherein the body of the microreactor is made of glass.