One frequently comes across expressions in academic writing such as the following: "Access to finance is key to supporting the world's poor."
Is this Standard English? Wouldn't it be more correct to say "Access to finance is a key factor in supporting the world's poor"?
I place this verbalization of the noun "key" in the same category as when one verbalizes the adjective "enthusiastic" to "enthuse" in the sentence, "The teenagers enthused about the hit songs of their pop idol."
I think the use of "key" like that would be fairly well understood and accepted and not thought of as slang or jargon.