Which of the following compounds fits the proton NMR shown below?

Which of the following compounds gives a 1H NMR spectrum consisting of only a singlet?

Which of the following compounds has the most signals in the proton-decoupled 13C NMR spectrum?

Which is the most acidic hydrogen?

A compound with molecular formula C8H19N exhibits a triplet at δ 0.9 (6H), a singlet at δ 1.1 (1H), a sextet at δ 1.3 (4H), a quintet at δ 1.4 (4H) and a triplet at δ 2.6 (4H) in its 1H NMR spectrum. Its IR spectrum shows a medium absorption band near 3400 cm-1. Its 13C NMR spectrum showed peaks at δ 13.7, δ 20.5, δ 30.4 and δ 49.2. What is the IUPAC name of this compound?

Which one of the following represents the HOMO of 1,3,5-hexatriene?

Which of the following energy diagrams represents the electronic state of the ground state of 1,3-butadiene?

What diene and dienophile are used in a Diels-Alder reaction to prepare the following compound?

Identify the allylic halide(s).

Which of the following compounds absorbs the longest wavelength of UV-visible light?