Meta tag and Latin Languages: to use or not to use special characters on metatags?

Meta tag and Latin Languages like spanish & portuguese -

as far as latin languages are concerned what works best :

1- To use special characters inside meta name keywords and description :

meta name=“keywords” content=" "
meta name=“description” content=" "

Let´s suppose the words to be included on meta tags are :

Clínica ortodôntica São Paulo ;

what is the correct way to write it , this way :

Cl & I acute ; nica ortod & ocirc ; ntica S & A tilde ; o Paulo …
(spaced deliberately so that it will appear in this forum )

2- …Or simply omit all stress accents and write it clear as the following :

Clinica Sao Paulo ???

How the spiders behave with latin languages ?