Abstract The 12.1 eV, 75 C electron impact mass spectra of 24 urethanes, RNHCO 2 C 2 H 5 [R [DOUBLE BOND] H, C 2 H 2n+ 1 (n= 1-8), CH 2 [DOUBLE BOND] CHCH 2, Ph, PhCH 2 and PhCH 2 CH 2], and seven symmetrically disubstituted urethanes R 2 NCO 2 C 2 H 5 (R [DOUBLE BOND] C n H 2n+ 1 (n= 1− 4)) are reported and discussed. All 31 spectra show appreciable molecular ion peaks. For n− Cn H 2n+ 1 NHCO 2 C 2 H 5, M+ usually is the ...
