There are chemistry journals for just about every fields and areas of chemistry you can think of at the moment. In fact I think we have too many!!!. What we need are top reputable journals, not more and more of irrelevant and insignificant journals. Narrowly specific journals often struggle to attract high quality articles.
Thank you Prof. Samuel for your answer. If it is about now attracting high-quality research papers, the question should now be about how some journals in chemistry eventually could close? :)
Nano-chemistry brings new interface and a revolution in size, portability, replenishing the demand of small size designed product and technologies. because of these factors, its papers are able to find peer reviewed high impact factor (IF).
Whereas medicinal Chemistry belongs to medicine and drug discovery category which cover different scope- useful organic synthesis, methods of getting generic drugs as compare to branded drugs which are much costlier in price, Formulation and computer aided drug design, etc. As medicinal chemistry is related to the health of the people therefore it is in trend and this helps its paper to find high IF's journals.
Although there are certainly other chemistry like geochemistry etc which are also demanding.
Thank you Arvid for your answer. Yes, The field of Nano is new, and it is a remarkably growing field. I am writing this because my background in materials engineering. I am not quite familiar with medicinal chemistry (which might belong more to pharmacy?)