Can I deduct unreimbursed business expenses like upgrades on airlines to business class, extra cost for choosing seats and Kenneling of pets
No, you cannot deduct the cost or upgrades or choosing seats; they are considered personal and are not deductible. The IRS only allows ordinary and necessary expenses as a business deduction... expenses that are common and accepted in your trade or business. Upgrading to a business class is not really considered ordinary and the IRS specifically disallows deducting expenses that are lavish or extravagant or expenses that are not directly related to your business.
As to kenneling of pets... are you in a business of transporting animals? If so, then yes, you can deduct the costs of kenneling. If that is your personal pet, then no, it is a personal expense and is not tax deductible.