A bit of research seems to indicate what the OP was suggesting will not be deductible.
"Sec. 170(f)(3) generally denies a charitable deduction for contributions of less than the donor's entire property interest. However, a deduction would be allowed under Sec. 170(f)(3)(B)(ii) for a contribution of a partial interest if it consists of the donor's entire interest in the property (unless the property in which such partial interest exists was divided to create such interest). Also, a deduction would be allowed if the taxpayer contributes an undivided portion of its entire property interest. "