It looks like you're trying to build a style guide. If so, then you really need to work closely with your UI designer to define/refine the colour palette and its usage.
Style guides protect you from team, supplier or product changes. If you get a new requirement from the product owner, the style guide should tell you how it will look. If you have to scale up your production and have to on-board a whole new team of designers or developers, the style guide will tell them how to design or build everything. They are the rulebook for designing and building anything to do with your product.
Your designer should be able to help you construct a guide that ensures reusability as well as extensibility - Ideally, as a part of that guide, you will end up with a palette of colours and a list of uses for those colours which your developer can turn into a set of colour definitions and a set of styles referencing those definitions.
Look around the web for examples of product or brand style guides but remember that, although they may occasionally share some similarities, every style guide for every product will have different requirements and so will have different levels of proscription and different levels content.
What you have so far is fine as a stop-gap, and it will help to streamline the connection between the designer and the developer, but you really should be working on this as a part of the overall product design rather than just as a solution for your developers. This should be one of your key project deliverables, almost as valuable as the product itself.