[cobaltwater]

Hi. I'm new to the forum but I'd welcome any and all help with regards to this compound identification.

It's a solid with large white crystals, brownish tint, almond-like odor. MP approx. 42 degrees. Schiff's and chromic acid tests were ambiguous. Tollens was positive but I'm doubting it's an aldehyde for reasons I'll mention.

A 2,4-dinitrophenylhydrazone derivative was prepared. It was solid with fine crystals and bright vermilion in color, with a MP of 210-220 deg. This leads me to believe it's an aromatic compound.

Major IR peaks: 3010, 2929, 2851, 2360, 2341, (aromatic overtones), 1700, 1610, 1456, 1396, 1275, 1201, 1173, 1034, 1014, 769 (strongest peak), 569

HNMR: 1H singlet at 2.1, 11H singlet at 2.7, 11H singlet at 3.3, 1H singlet (?) at 7.3, 8H triplet at 7.4, 8H singlet at 7.7 (note: no indicative aldehyde signals past 9 ppm, peak integrations may not be accurate)

CNMR: peaks at 25, 37, 123, 126, 127, 133, 136, 155, 208 (9 signals)

DEPT CNMR: negative peaks at 25, 37; positive peaks at 123, 126, 127, 133

MS: M+ at either 132 or 133, first significant fragment is 28 or 29 amu (second is 54 or 53)

Since the carbonyl signal is present at about 1700, and there are aromatic overtones, it's either a normal aromatic ketone or aromatic aldehyde. The HNMR and CNMR leads me to believe it is a meta-substituted aromatic ketone (though I'm not familiar with many *solid* ketones). I'm not sure exactly which, though it looks like the remainder should be C2H4 after accounting for the phenylketone portion. But the compounds I looked up after this look nothing like my compound.

The gist of the problem is that I have some evidence pointing toward an aromatic ketone that's meta-substituted (disparity between number of peaks in DEPT and normal CNMR, that strong 787 peak in IR), but on the other hand there's evidence that the other group on the carbonyl carbon is a vinyl group (the loss of 28 m/z in MS). There's something I'm missing to make this compound work but I don't know exactly what.