There are a few relevant questions here:
How will your future grad school applications be treated if your eventual degree is chemistry
How do you get to know better that quantum computing as a field will be where you can best pursue your career
How do you prepare yourself better for pursuing a career in quantum computing
I am going to talk about the last one.
I'll organize the things you can do into 2 categories: research & study.
You should try to find research internship in quantum computing. Various countries have their own scholarship system for undergrad participating in research where the funding contribution requirement from the PI is minimal. Look those up. Often, even if you study in Netherland, there is no restriction for you to apply to, say, a Canadian department via NSERC's scholarship program.
Your eventual goal (while in undergrad) should be to have publication(s) before the end of undergrad or come close to it. If you are one of the authors of a good quality paper, I would hazard to guess that your degree title won't be a problem with any admission committee. (Do check with ppl with actual admission committee experience. I don't.)
With that, as you search for research groups that interest you, you can ask what background a specific research group would need from you for you to do an undergrad project with them. Between the PI and the department, they will also be able to tell you how you can be competitive in getting the scholarship and the placement.
Typically, good overall grade at your current program is required. And then there will be other things. So, keep your grades good. Drop courses you strongly dislike early to avoid tanking your grade, for example. Those other things likely include courses relevant to the research topic you will propose with the PI. That's why your course load should likely be different from a typical chemistry major. A side-effect is: if you missed some chemistry courses that another student would have at the same year at your institute, it won't be noticed.
If and when you do interact with researchers in this manner, do specifically ask what review paper or conference presentation or other introductory materials they would recommend for you to understand the related areas for quantum computing -- in order for you to guide your study before switching degree/institution. For example, obviously theoretical computer science is related. Theoretical computer science, however, is a large and diverse field. Studying theoretical computer science topics broadly will get you nowhere in terms of pursuing a career in quantum computing (other than getting you smarter, which I suppose could be limitless in itself; but let's not be pedantic here.)
The second half about mentioning that you would like guidance before switching degree/institution leads to the next point I will comment.
Switching degree/institution for an intellectual pursuit is admirable. Hopefully people will relate to that. They will also hopefully understand its gravity and therefore understand why you would need their guidance in the first place -- as opposed to from your own institute and your own degree program.
The gravity part should be understood by yourself as well.
How do you know quantum computing is for you? How do you know more whether you will be successful in quantum computing?
I'll leave that to yourself and others. I think getting to know more about quantum computing and the contributing disciplines will help. So let's talk about those.
I would suggest you start taking some math courses: linear algebra and real analysis. Linear algebra courses can often be matrix algebra in reality. You need exposure to the theory side of linear algebra.
As with any other subjects, you can potentially take a more applied course and supplement with your own study to gain exposure to the theory side. And you can ask subject-specific questions separately. e.g. "which textbooks are good if I want to understand the theories behind linear algebra with an eye on applications to quantum mechanics and quantum computing". And then people may answer: Friedberg, Hoffmann. etc.
You should also try to take quantum theory courses. Your introductory quantum mechanics course likely focused on hydrogen atoms and the solution to Schrodinger's equation with harmonic potential. You should ask separate questions on what "quantum theory" would entail. But say, why should Schrodinger's equation even be valid in the first place and why does it have the form it does? Maybe a quantum theory course would cover materials necessary to answer such questions.
I would also suggest taking some lab courses in physics. Many things in that umbrella can help actually. You should ask a separate question as usual.
Some computer science courses may help. Same with information theory. Statistics. The list can go on. The issues with these subjects though is that I would expect the relevant courses for you have tons of pre-requisite that are not relevant for you. That's why I don't recommend them. You can also ask a separate question like "what computer science courses should I take to help pursue a career in quantum computing" etc.
Note that thus far I have not mentioned anything about alternative degree. One quick tip first: keep an eye out for degree programs at your institute that have requirements that are close to the courses that you eventually shortlist for yourself. That could be how you find the degree to switch into.
Other than the above tip, my advise is actually: you do not have to switch degree before you start to prepare. You can first prepare and explore before you eventually switch degree or even institute.
You prepare by knowing more about quantum computing and gaining hard skills/knowledge that are foundational to quantum computing. The eventual goal (in undergrad) for you should be to get research scholarships and be a part of a research publication.
The emphasis on plural here is intentional. Research can be hard. It can take you a few internship to be productive eventually.
So start prepping early!
I guess, that's a good ender.
