Abstract: The current invention offers a process for the production of N-Boc-2-amino-3,3-dimethylbutyric acid by a reaction of tert-Leucine with di-tert-butyl-dicarbonate, the process comprising (i) contacting the tert-Leucine with di-tert-butyl-dicarbonate in an aqueous medium, optionally comprising a first organic solvent, in the presence of an inorganic base, (ii) optionally removing the first organic solvent, (iii) optionally extracting the resulting N-Boc-2-amino-3,3-dimethylbutyric acid into a second organic solvent, (iv) isolating the product by precipitation from the reaction mixture at acidic pH, and (v) optionally reuse the first and/or second organic solvents recovered from step (ii) and/or step (iv) for the next production cycle. The process is sufficiently short, uses preferably environmental friendly solvents, avoids waste and leads to good yields.

Abstract: The present invention discloses a method of manufacturing 4-chloro-7H-pyrrolo[2,3-d]pyrimidine comprising the steps: a) Preparing ethyl 2-cyano-4,4-dimethoxybutanoate by coupling ethyl 2-cyanoacetate and 2-bromo-1,1-dimethoxyethane; b) Preparing 6-amino-5-(2,2-dimethoxyethyl)pyrimidin-4-ol by adding formamidine to ethyl 2-cyano-4,4-dimethoxybutanoate; c) Converting 6-amino-5-(2,2-dimethoxyethyl)pyrimidin-4-ol to 7H-pyrrolo[2,3-d]pyrimidin-4-ol; and d) Converting the 7H-pyrrolo[2,3-d]pyrimidin-4-ol to 4-chloro-7H-pyrrolo[2,3-d]pyrimidine. The method offers increased yield, less by-products and a decrease in waste compared to methods known as being state of the art.

Abstract: The current invention offers a process for the production of N-Boc-2-amino-3,3-dimethylbutyric acid by a reaction of tert-Leucine with di-tert-butyl-dicarbonate, the process comprising (i) contacting the tert-Leucine with di-tert-butyl-dicarbonate in an aqueous medium, optionally comprising a first organic solvent, in the presence of an inorganic base, (ii) optionally removing the first organic solvent, (iii) optionally extracting the resulting N-Boc-2-amino-3,3-dimethylbutyric acid into a second organic solvent, (iv) isolating the product by precipitation from the reaction mixture at acidic pH, and (v) optionally reuse the first and/or second organic solvents recovered from step (ii) and/or step (iv) for the next production cycle. The process is sufficiently short, uses preferably environmental friendly solvents, avoids waste and leads to good yields.

Abstract: The present invention discloses a method of manufacturing 4-chloro-7H-pyrrolo[2,3-d]pyrimidine comprising the steps: a) Preparing ethyl 2-cyano-4,4-dimethoxybutanoate by coupling ethyl 2-cyanoacetate and 2-bromo-1,1-dimethoxyethane; b) Preparing 6-amino-5-(2,2-dimethoxyethyl)pyrimidin-4-ol by adding formamidine to ethyl 2-cyano-4,4-dimethoxybutanoate; c) Converting 6-amino-5-(2,2-dimethoxyethyl)pyrimidin-4-ol to 7H-pyrrolo[2,3-d]pyrimidin-4-ol; and d) Converting the 7H-pyrrolo[2,3-d]pyrimidin-4-ol to 4-chloro-7H-pyrrolo[2,3-d]pyrimidine. The method offers increased yield, less by-products and a decrease in waste compared to methods known as being state of the art.