1. I think the very first step should be measuring the degree of unsaturation. 2. For ensuring which one is e/f, you can go for chemical shift calculation.
Man, I just found your videos and they are really good, you talk very clearly and show every step of the thinking behind the problem. I was searching for videos like that so I could see someone actually working on determining structures from spectra and it helped me a lot. About the UV, it's probably just confirming the existence of conjugation, I think. The more conjugated the molecule, the higher the max wavelength it absorbs in UV-VIS region. The spectra shows an absorption at 260 nm, so it must have some conjugation, but not too much as it falls in the UV region, not in the VIS.
That was pretty helpful. Though you can note that an odd electron ion or an even mass fragment (here it’s at m/z 122) formed through fragmentation of an even mass molecule would result from a rearrangement. This rearrangement here is McLafferty concerted rearrangement that would happen when a gamma sp3-hybridized carbon has a hydrogen atom that transfers to the heteroatom (here it’s the oxygen) with alpha-beta bond to the double bond being cleaved. Note that for an ester it’s a special case rearrangement considering the oxygen atom of the alcohol chain to be alpha with respect to the double bond. Hope this helps.
Hello sir I'm from Pakistan..I want to ask about the solving all the spectrum with concluding result..I mean I want to use iR,HNMR,CNMR and Mass spectrum to conclude structure
Are you referring to the carbon NMR? Since this is a DEPT experiment, only the carbons that have H's bonded to them are showing up. It is not a normal carbon NMR! Hopefully this answers your question?