Understand that SEC179 is not an "expense" in the sense you may think it is. The SEC179 deduction is a method that allows you to depreciate business assets 100% in the first year of business. This is only beneficial if you actually have the taxable business income to depreciate such assets against. Whenever you sell or otherwise dispose of such assets, the depreciation has to be accounted for in the tax year of sale or disposition. So if you fully deducted the cost of an asset under SEC 179 in that first year, and then you sold it the next year, your cost basis on that asset would be $0. That means that whatever you sold it for would be considered taxable income. If you donated the property to a qualified charity, then your donation value would be $0, since you would have already taken a deduction for the cost of the asset under SEC 179.
Additionally, business assets that cost less than $5000 and are not classified as real estate (along with a few other criteria) can just be expensed. Period. Nothing to do with depreciation or SEC179. You just write them off as a business expense under IRC section 263(a) and you're done with it forever. This is referred to as safe harbor de-minimus. You ca read about it at https://www.irs.gov/businesses/small-businesses-self-employed/tangible-property-final-regulations. Note that if you take the de-minimus deduction you will not be able to e-file the return for that tax year, as you are required to mail it in along with a statement of what you're doing.
