The present paper covers a new process for the synthesis of 1-（2,6,6-trimethyl-1-cyclohexenyl）-3-methyl-2-buten-4-al with dimethyl sulfide, bromomethane and β-ionone as primary materials in four steps, via the carb...The present paper covers a new process for the synthesis of 1-（2,6,6-trimethyl-1-cyclohexenyl）-3-methyl-2-buten-4-al with dimethyl sulfide, bromomethane and β-ionone as primary materials in four steps, via the carbine reaction of dimethyl sulfide and bromomethane, the cyclization of trimethylsulfonium bromide and β-ionone, the opening of epoxy compound and isomerization of C14-aldehyde. The overall yield is 77%. The structure of the titled product was characterized by GC/MS, IR and 1H NMR. The process has many advantages such as facile low-cost materials, high conversion, short reaction time, mild reaction ondition, and less by-products. Furthermore, the part materials can be recycled, the cost and pollution are reduced, so it is feasible for industry production.展开更多
The method for synthesis of the title compound has been improved, with product yield being increased to 58%. The following measures have been adopted: using 1,8-diazabicyclo\undec-7-ene(DBU) as catalyst instead of pip...The method for synthesis of the title compound has been improved, with product yield being increased to 58%. The following measures have been adopted: using 1,8-diazabicyclo\undec-7-ene(DBU) as catalyst instead of piperidine; adding benzene in the reaction mixture to favor azeotropic dehydration. The optimum molar ratio of DBU/ethylacetoacetate/solid paraformaldehyde was 4∶20∶11.展开更多
文摘The present paper covers a new process for the synthesis of 1-（2,6,6-trimethyl-1-cyclohexenyl）-3-methyl-2-buten-4-al with dimethyl sulfide, bromomethane and β-ionone as primary materials in four steps, via the carbine reaction of dimethyl sulfide and bromomethane, the cyclization of trimethylsulfonium bromide and β-ionone, the opening of epoxy compound and isomerization of C14-aldehyde. The overall yield is 77%. The structure of the titled product was characterized by GC/MS, IR and 1H NMR. The process has many advantages such as facile low-cost materials, high conversion, short reaction time, mild reaction ondition, and less by-products. Furthermore, the part materials can be recycled, the cost and pollution are reduced, so it is feasible for industry production.
文摘The method for synthesis of the title compound has been improved, with product yield being increased to 58%. The following measures have been adopted: using 1,8-diazabicyclo\undec-7-ene(DBU) as catalyst instead of piperidine; adding benzene in the reaction mixture to favor azeotropic dehydration. The optimum molar ratio of DBU/ethylacetoacetate/solid paraformaldehyde was 4∶20∶11.
