Question

please draw $\pi$ orbitals of (1,4-Pentadiene(unconjugated) and 1,3-butadiene(conjugated)) (MOT) and compare their stabilty.

and please draw MO of 1,3 pentadiene by MOt

Answer 1

TT osbtal diagdam a 4-pertadiene (ancorgaa and 1zttadene Garugated) 13-btadiene cooggatd 11 Apustadiene Cancomugatea

In 1,3-butadiene pi bonds are conjugated and planar , conjugated dienes are stable due to delocalisation of pi electrons along the sp² hybredised orbital and this leads to lower energy and greater stability but in the case of 1,4-pentadiene (unconjugated) delocalisation of pi electron is lost due to sp³ hybredised carbon present in between pi bonds this leads to less stability for 1,4-pentadiene (unconjugated) compared to 1,3-butadiene.

MO diagram of 1,3 - pentadiene :

Mole cadas osbital diapam jo the Butadienyl Syotion ,3 buradiene Ccampuzated is No o4 T electsons = 4 3 we have to constsuct the Mo diaaam 13 buta diene Sadem, so we cwill areange thi axbitals the ineeasi eneag that u give the follouing diagsarm Nodes TA enjeagy Lawnst unoclupied maleculacs oabtal LUMO Energy 4 Hig hest occaupied Molecules obl TT2 HOMO LouRst enegy