First of all, how do you know your reaction even worked? Did you do TLC to confirm formation of new species and disappearance of starting material?

Secondly, tert butyl peaks are usually at 1.26 and i see big peak at 1.28.

@Greg yes i have done the TLC and getting mass peak also in ESI-MS.

I believe i see the tert butyl peak at 1.28

your integration seems off though.

hi , there the peak appear at 1.28 mostyl announce tert butyl , but sometimes the NMR read a part of the compound twice as in case of z and E , so the integration isnt precise , this problem occured with me as i work with tert buty as side chain and protoective group.

if the mass spectra is correlated to your compund and c13 nmr is ok its fine

thanks and regards