( ( ( R 2 ) ( Secondary alcohols ) ) ( ( can ( be ( oxidized ( to ketones ) ) ) ) . ) )
(ROOT (S (NP (QP (CD R) (CD 2)) (JJ Secondary) (NNS alcohols)) (VP (MD can) (VP (VB be) (VP (VBN oxidized) (PP (TO to) (NP (NNS ketones)))))) (. .)))
R 2 Secondary alcohols can be oxidized to ketones.
(ROOT (S (NP (JJ Secondary) (NN alcohol)) (VP (VBZ forms) (NP (DT a) (NN ketone)) (SBAR (WHADVP (WRB when)) (S (VP (VBD oxidized))))) (. .)))