Are you Self-Employed or do you have a corporation, partnership?
Partners can agree among themselves as to how income, losses, and gains will be divided among the partners. For instance, you can claim 100% of the losses and your partner can claim 100% of the income. Any agreement is possible. If there is no partnership agreement, then income, losses and gains are allocated proportionally based on the partnership interests of each partner. The partners then report the allocated amount on their individual income tax returns and pay taxes accordingly. It's best to talk to an accountant or attorney to set something like this up. Hope this is helpful.
If you are not in business yourself, donations need to be made to qualified charitable organizations. These are organizations that have been granted tax-exempt status by the IRS and are eligible to receive tax-deductible charitable contributions. Donations or gifts to an individual or any organization that is not tax-exempt are not deductible.
Examples of qualified charitable organizations:
If you're not sure of the organization's charitable status, contact them directly or use the IRS Exempt Organizations Lookup Tool.
Sometimes, however, businesses that have received some benefit for the donation (ad space or marketing, for example) may deduct the payment as a business expense on a business return.
If you've provided capital towards a new business entity, it would seem that you could/should have an equity stake in the business. Otherwise, it's just a non-deductible gift.
Please feel free to post any additional details or questions in the comment section.