The patent entitled “Process for the Synthesis of 4-(dimethylsilane)-alkylferrocene”.  The inventors of this patent are Prof. Tushar Jana (School of Chemistry, UoH and adjunct faculty in ACRHEM) and Dr. Bikash Kumar Sikder (who worked as a post-doctoral fellow in ACRHEM with Prof. Jana)

 

The Advanced Centre of Research in High Energy Materials (ACRHEM) – a DRDO Centre of Excellence in University of Hyderabad (UoH) has been granted a patent entitled “Process for the Synthesis of 4-(dimethylsilane)-alkylferrocene”.  The inventors of this patent are Prof. Tushar Jana (School of Chemistry, UoH and adjunct faculty in ACRHEM) and Dr. Bikash Kumar Sikder (who worked as a post-doctoral fellow in ACRHEM with Prof. Jana).    

Prof. Tushar Jana

Ferrocene and its derivatives have been found important for use in catalysis, nanomaterials, pharmaceutical industries etc. Apart from these, ferrocene derivatives have been extensively used as potential burn rate enhancers (BRC) in composite propellants. In order to do so, ferrocene derivatives should possess certain inherent properties such as good microscopic homogeneities and compatibility with the other ingredients, particularly with the binder system. It should not adversely migrate or deteriorate mechanical properties on storage, retain shelf life, sensitivity and ageing stability even when present at high concentration.

Dr. Bikash Kumar Sikder

Driven by the above mentioned properties, various research groups across the globe have directed their research towards exploring and developing the use of BRC in composite propellants, but, most of these ferrocene derivatives displayed certain inherent drawbacks, such as, migration on storage where it travels out of the binder matrix into the surrounding insulating material, decreased shelf life, deteriorated mechanical properties, poor ageing behaviour, affecting desired burning parameters, or resulted in an intense explosion.

The first successful attempt was the development of “organic silicon ferrocene derivatives” by “Societe Nationale des Poudres et Explosifs (SNPE), France”. 4-(dimethylsilyl) butylferrocene was then selectively grafted into hydroxy terminated polybutadiene (HTPB) to obtain a liquid resin and was commercialized under the trade name of “Butacene 800®”. For this, however, there exist a few research reports that point to several concerns such as the use of toxic or corrosive chemicals, stringent reaction conditions or purification process and most importantly, that it didn’t address a process for the synthesis of structural variants of 4-(dimethylsilyl) butylferrocene.

In view of the above drawbacks, there was a need for developing an improved process for preparation of 4-(dimethylsilyl)-alkylferrocene. The present patent deals with the invention of a cost effective, simple and efficient synthetic process for the synthesis of 4-(dimethylsillane) butylferrocene. It also offers a process for the synthesis of structural variants of 4-(dimethylsilyl) alkylferrocene which can be easily scalable up to industrial scale.