( ( In ( organic chemistry ) ) ( , ( ( an ( electrocyclic reaction ) ) ( ( is ( ( ( a type ) ( of ( pericyclic rearrangement ) ) ) ( where ( ( the ( net result ) ) ( is ( ( one ( pi bond ) ) ( being ( converted ( into ( ( ( one ( sigma bond ) ) or ) vice-versa ) ) ) ) ) ) ) ) ) ) . ) ) ) )
(ROOT (S (PP (IN In) (NP (JJ organic) (NN chemistry))) (, ,) (NP (DT an) (JJ electrocyclic) (NN reaction)) (VP (VBZ is) (NP (NP (DT a) (NN type)) (PP (IN of) (NP (JJ pericyclic) (NN rearrangement))) (SBAR (WHADVP (WRB where)) (S (NP (DT the) (JJ net) (NN result)) (VP (VBZ is) (NP (NP (CD one) (NN pi) (NN bond)) (VP (VBG being) (VP (VBN converted) (PP (IN into) (NP (NP (CD one) (NN sigma) (NN bond)) (CC or) (NP (NN vice-versa)))))))))))) (. .)))
In organic chemistry, an electrocyclic reaction is a type of pericyclic rearrangement where the net result is one pi bond being converted into one sigma bond or vice-versa.
(ROOT (S (NP (DT A) (JJ double) (NN bond)) (VP (VBZ consists) (PP (IN of) (NP (NP (CD one) (NN sigma) (NN bond)) (CC and) (NP (CD one) (NN pi) (NN bond))))) (. .)))