[paranitro]

Hello everyone.

I could not find a "photochemistry" forum so I thought this forum is the most appropriate for my question.  I synthesized a compound and accidentally discovered that it has some unknown photochemistry, can anyone help me with this?

The compound is N-(3-(4-nitrophenyl)propyl)dodecan-1-amine (molecular weight of 348.3). When I photolyze it, it breaks into two at the nitrogen in the middle giving me either N-3-(4-nitrophenyl)propylamine, dodecylamine, N-3-(4-nitrophenyl)propane or dodecane based on mass spec. Anyone want to speculate on what mechanism this might be occurring?

Much appreciated.

[zolarpwr]

How do you know there is really photochemistry happening? Color change? TLC? NMR evidence?

Depending on the ionization method, even perfectly stable compounds undergo fragmentation during mass spectral analysis. Hopefully observing the fragments isn't your only indication that you think your compound is decomposing.

2- and 4-nitrobenzyl ethers and esters do undergo cleavage by light, eliminating the alkoxide or carboxylate. Maybe your reaction is related.

[paranitro]

zolarpwr,

Thanks for responding.

How do you know there is really photochemistry happening? Color change? TLC? NMR evidence?

I have checked HPLC after photolyzing the compound and performed mass spectrometry (with the control sample, i.e. no light) to show that the compound is no longer the intact parent molecule.  Also, the compound also changed color after photolysis.

Depending on the ionization method, even perfectly stable compounds undergo fragmentation during mass spectral analysis. Hopefully observing the fragments isn't your only indication that you think your compound is decomposing.

The control (without light) under the same ionizing condition did not give the same fragmentation pattern.  The intact molecule is still present 100%.

2- and 4-nitrobenzyl ethers and esters do undergo cleavage by light, eliminating the alkoxide or carboxylate. Maybe your reaction is related. 

I will have to check this out.

Thanks.