Depends.
The generic term is “promotional materials” or (somewhat obnoxiously) “promos.” That’s the term used within the finance industry and their regulators and covers everything from informational brochures to free tchotchkes to coupons. It’d be the go-to expression for the guys putting them all together. Similarly, educational material and gifts not inclusive of a propaganda mission are known as “non-promotional materials.”
There’s no good reason not to call them “gifts” or (somewhat more obnoxiously) “complimentary gifts” if you’re giving them away freely and not expecting a direct quid-pro-quo in response. They are gifts and it’s a nicer word to use as you’re handing them out, unless you’re deliberately trying to undermine the promotion by dismissing it all as useless hype (possibly to come across as the “cool” guy in marketing).
The people receiving the gifts often call them “swag”
Items given away free, typically for promotional purposes, to people attending an event, using a service, etc.
It’s especially common in reference to, e.g., the very nice “swag bags” of gifts received by movie stars visiting various marketing venues during Oscar season so it comes with some cachet. You’d particularly use it if you wanted to talk up the gifts as desirable. [Edit: In the comments above, FumbleFingers mentions “goodies:” it’s essentially synonymous with “swag” and is another nice word to use to talk up the promotional material you’re giving away. Swag bags are also known as “goody” or “goodie bags.”]
If you wanted to be realistic or talk them down, there’s the Yiddishy “schwag” (associated with low-grade marijuana), cheap-sounding “freeby” or “freebie” (associated with NSA sex), or—when you’re being completely frank and the manager isn’t listening—“useless crap” (associated with bloatware). If what you’re giving away are low-quality T-shirts, stationery, and business-slogan posters, some synonym of useless crap (here or here) is probably what most of the employees are calling them. My personal favorite is “pony” (British rhyming slang: “pony-and-trap” → “crap”) but no one would understand that; you could use it as your own office lingo for the stuff.