The following mass spectra are of fatty acid esters other than methyl.
Such fatty acid derivatives can be useful for some analytical purposes, and the spectra can often be of value in explaining fragmentation patterns.
Some, such as the wax esters, occur naturally.
The spectra can be accessed directly from the tabulated links below, or by scrolling down.
No comments or interpretation are provided here, as the general principles for most are discussed elsewhere in these web pages.
Further spectra are added as they become available.
The source of each fatty acid listed is that from which I obtained the spectrum in the course of my research efforts,
not necessarily the optimum source.
Free (unesterified) fatty acids |
| Fatty acid |
M+ |
Fatty acid |
M+ |
| |
| butyric (4:0) |
88 |
heptadecanoic (17:0) |
270 |
| hexanoic (6:0) |
116 |
octadecanoic (18:0) |
284 |
| octanoic (8:0) |
144 |
9-tetradecenoic (9-14:1) |
226 |
| decanoic (10:0) |
172 |
3-octadecenoic (3-18:1) |
282 |
| undecanoic (11:0) |
186 |
6-octadecenoic (6-18:1) |
282 |
| dodecanoic (12:0) |
200 |
9-octadecenoic (9-18:1) |
282 |
| tridecanoic (13:0) |
214 |
11-octadecenoic (11-18:1) |
282 |
| tetradecanoic (14:0) |
228 |
9,12-octadecadienoic (9,12-18:2) |
280 |
| pentadecanoic (15:0) |
242 |
9,12,15-octadecatrienoic (9,12,15-18:3) |
278 |
| hexadecanoic (16:0) |
256 |
3,4-tetradecadienoic acid |
224 |
Lactones
|
| 4-hydroxy-decanoate - gamma-lactone |
170 |
4-hydroxy-dodecanoate - gamma-lactone |
198 |
| |
| 5-hydroxy-decanoate - delta-lactone |
170 |
5-hydroxy-hexadecanoate - delta-lactone |
254 |
| 5-hydroxy-dodecanoate - delta-lactone |
198 |
5-hydroxy-octadecanoate - delta-lactone |
282 |
| 5-hydroxy-tetradecanoate - delta-lactone |
226 |
5-hydroxy-eicosanoate - delta-lactone |
310 |
Ethyl esters of fatty acids
|
| Fatty acid |
M+ |
Fatty acid |
M+ |
| |
| hexanoate (6:0) |
144 |
|
|
| octanoate (8:0) |
172 |
tricosanoate (23:0) |
382 |
| decanoate (10:0) |
200 |
tetracosanoate (24:0) |
396 |
| dodecanoate (12:0) |
228 |
hexacosanoate (26:0) |
424 |
| tetradecanoate (14:0) |
256 |
|
|
| pentadecanoate (15:0) |
270 |
13-methyltetradecanoate (iso) |
270 |
| hexadecanoate (16:0) |
284 |
14-methylhexadecanoate (anteiso) |
298 |
| heptadecanoate (17:0) |
298 |
15-methylhexadecanoate (iso) |
298 |
| octadecanoate (18:0) |
312 |
|
|
| nonadecanoate (19:0) |
326 |
4,8,12-trimethyltridecanoate |
284 |
| eicosanoate (20:0) |
340 |
2,6,10,14-tetramethylpentadecanoate (pristanate) |
326 |
| docosanoate (22:0) |
368 |
3,7,11,15-tetramethylhexadecanoate (phytanate) |
340 |
| |
| 9-tetradecenoate (9-14:1) |
254 |
3-trans-eicosenoate (3t-20:1) |
338 |
| 7-hexadecenoate (7-16:1) |
282 |
5-eicosenoate (5-20:1) |
338 |
| 9-hexadecenoate (9-16:1) |
282 |
11-eicosenoate (11-20:1) |
338 |
| 9-heptadecenoate |
296 |
5-docosenoate (5-22:1) |
366 |
| 3-trans-octadecenoate (3t-18:1) |
310 |
13-docosenoate (13-22:1) |
366 |
| 5-octadecenoate (5-18:1) |
310 |
15-tetracosenoate (15-24:1) |
394 |
| 9-octadecenoate (9-18:1) |
310 |
|
|
| 11-octadecenoate (11-18:1) |
310 |
7-methyl-hexadec-6-enoate |
296 |
| |
| 9,12-hexadecadienoate (16:2(n-4)) |
280 |
9,12-octadecadienoate (18:2(n-6)) |
308 |
| 3-trans,9-cis-octadecadienoate (3t,9c-18:2) |
308 |
10,13-nonadecadienoate (19:2(n-6)) |
322 |
| 5,9-octadecadienoate (5,9-18:2) |
308 |
3-trans,11-cis-eicosadienoate (3t,11c-20:2) |
336 |
| 5,11-octadecadienoate (5,11-18:2) |
308 |
11,14-eicosadienoate (20:2(n-6)) |
336 |
| 9-cis,11-trans-octadecadienoate |
308 |
5,13-docosadienoate (5,13-22:2) |
364 |
| |
| 6,9,12-hexadecatrienoate (16:3(n-4)) |
278 |
11,14,17-octadecatrienoate (18:3(n-1)) |
306 |
| 3t,9c,12c-octadecatrienoate (3t,9c,12c-18:3) |
306 |
|
|
| 5,9,12-octadecatrienoate (5,9,12-18:3) |
306 |
3t,11c,14c-eicosatrienoate (3t,11c,14c-20:3) |
334 |
| 6,9,12-octadecatrienoate (18:3(n-6)) |
306 |
5,8,11-eicosatrienoate (20:3(n-9)) |
334 |
| 8,11,14-octadecatrienoate (18:3(n-4)) |
306 |
5,11,14-eicosatrienoate (5,11,14-20:3) |
334 |
| 9t,11t,13t-octadecatrienoate (9t,11t,13t-18:3) |
306 |
10,13,16-eicosatrienoate (20:3(n-4)) |
334 |
| 9,12,15-octadecatrienoate (18:3(n-3)) |
306 |
11,14,17-eicosatrienoate (20:3(n-3)) |
334 |
| |
| 6,9,12,15-hexadecatetraenoate (16:4(n-1)) |
276 |
7,10,13,16-eicosatetraenoate (20:4(n-4)) |
332 |
| 3t,9c,12c,15c-octadecatetraenoate
(3t,9c,12c,15c-18:4) |
304 |
8,11,14,17-eicosatetraenoate (20:4(n-3)) |
332 |
| 6,9,12,15-octadecatetraenoate (18:4(n-3)) |
304 |
10,13,16,19-eicosatetraenoate (20:4(n-1)) |
332 |
| 8,11,14,17-octadecatetraenoate (18:4(n-1)) |
304 |
7,10,13,16-docosatetraenoate (22:4(n-6)) |
360 |
| 5,8,11,14-eicosatetraenoate (20:4(n-6)) |
332 |
10,13,16,19-docosatetraenoate (22:4(n-3)) |
360 |
| |
| 5,8,11,14,17-octadecapentaenoate (18:5(n-1)) |
302 |
4,7,10,13,16-docosapentaenoate (22:5(n-6)) |
358 |
| 4,7,10,13,16-nonadecapentaenoate (19:5(n-3)) |
316 |
7,10,13,16,19-docosapentaenoate (22:5(n-3)) |
358 |
| 5,8,11,14,17-eicosapentaenoate (20:5(n-3)) |
330 |
|
|
| 6,9,12,15,18-heneicosapentaenoate (21:5(n-3)) |
334 |
4,7,10,13,16,19-docosahexaenoate (22:6(n-3)) |
356 |
| |
| octadec-9-ynoate |
308 |
|
|
| 2,3-tetradecadienoate |
252 |
3,4-tetradecadienoate |
252 |
| |
| 11-cyclopentenylundecanoate |
280 |
13-cyclopentenyltridec-6-enoate |
306 |
| 13-cyclopentenyltridecanoate |
308 |
15-cyclopent-2-enylpentadec-9-enoate |
334 |
| 15-cyclopentenylpentadecanoate |
336 |
|
|
| |
| 10,13-epoxy-11-methyl-hexadecadienoate |
308 |
12,15-epoxy-13,14-dimethyl-octadecadienoate |
350 |
| 10,13-epoxy-11,12-dimethyl-hexadecadienoate |
322 |
12,15-epoxy-13-methyl-eicosadienoate |
364 |
| 10,13-epoxy-11-methyl-octadecadienoate |
336 |
12,15-epoxy-13,14-dimethyl-eicosadienoate |
378 |
| 10,13-epoxy-11,12-dimethyl-octadecadienoate |
350 |
14,17-epoxy-15,16-dimethyl-eicosadienoate |
378 |
| 12,15-epoxy-13-methyl-octadecadienoate |
336 |
|
|
n-Propyl esters of fatty acids |
| Fatty acid |
M+ |
Fatty acid |
M+ |
| |
| octanoate (8:0) |
186 |
9-octadecenoate (9-18:1) |
324 |
| decanoate (10:0) |
214 |
11-octadecenoate (11-18:1) |
324 |
| dodecanoate (12:0) |
242 |
11-eicosenoate (11-20:1) |
352 |
| tetradecanoate (14:0) |
270 |
13-docosenoate (13-22:1) |
380 |
| pentadecanoate (15:0) |
284 |
15-tetracosenoate (15-24:1) |
408 |
| hexadecanoate (16:0) |
298 |
|
|
| heptadecanoate (17:0) |
312 |
9,12-hexadecadienoate (16:2(n-4)) |
294 |
| octadecanoate (18:0) |
326 |
9,12-octadecadienoate (18:2(n-6)) |
322 |
| eicosanoate (20:0) |
354 |
9-cis,11-trans-octadecadienoate |
322 |
| |
| 4,8,12-trimethyltridecanoate |
298 |
6,9,12-hexadecatrienoate (16:3(n-4)) |
292 |
| 13-methyltetradecanoate (iso) |
286 |
9,12,15-octadecatrienoate (18:3(n-3)) |
320 |
| 2,6,10,14-tetramethylpentadecanoate (pristanate) |
340 |
6,9,12,15-octadecatetraenoate (18:4(n-3)) |
318 |
| 14-methylhexadecanoate (anteiso) |
312 |
5,8,11,14-eicosatetraenoate (20:4(n-6)) |
346 |
| 15-methylhexadecanoate (iso) |
312 |
8,11,14,17-eicosatetraenoate (20:4(n-3)) |
346 |
|
|
5,8,11,14,17-eicosapentaenoate (20:5(n-3)) |
344 |
| 9-tetradecenoate (9-14:1) |
268 |
7,10,13,16,19-docosapentaenoate (22:5(n-3)) |
372 |
| 9-hexadecenoate (9-16:1) |
296 |
4,7,10,13,16,19-docosahexaenoate (22:6(n-3)) |
370 |
iso-Propyl esters of fatty acids
|
| Fatty acid |
M+ |
Fatty acid |
M+ |
| |
| hexanoate (6:0) |
158 |
nonadecanoate (19:0) |
340 |
| octanoate (8:0) |
186 |
eicosanoate (20:0) |
354 |
| decanoate (10:0) |
214 |
heneicosanoate (21:0) |
368 |
| dodecanoate (12:0) |
242 |
docosanoate (22:0) |
382 |
| tetradecanoate (14:0) |
270 |
tricosanoate (23:0) |
396 |
| pentadecanoate (15:0) |
284 |
tetracosanoate (24:0) |
410 |
| hexadecanoate (16:0) |
298 |
hexacosanoate (26:0) |
438 |
| heptadecanoate (17:0) |
312 |
octacosanoate (28:0) |
466 |
| octadecanoate (18:0) |
326 |
triacontanoate (30:0) |
494 |
| |
| 8-methyl-decanoate (anteiso) |
228 |
15-methyl-docosanoate |
396 |
| 10-methyl-undecanoate (iso) |
242 |
20-methyl-docosanoate (anteiso) |
396 |
| 10-methyl-dodecanoate (anteiso) |
256 |
21-methyl-docosanoate (iso) |
396 |
| 12-methyl-tridecanoate (iso) |
270 |
22-methyl-tricosanoate (iso) |
410 |
| 12-methyl-tetradecanoate (anteiso) |
284 |
22-methyl-tetracosanoate (anteiso) |
424 |
| 13-methyl-tetradecanoate (iso) |
284 |
24-methyl-pentacosanoate (iso) |
438 |
| 14-methyl-pentadecanoate (iso) |
298 |
24-methyl-hexacosanoate (anteiso) |
452 |
| 14-methyl-hexadecanoate (anteiso) |
312 |
26-methyl-heptacosanoate (iso) |
466 |
| 15-methyl-hexadecanoate (iso) |
312 |
26-methyl-octacosanoate (anteiso) |
480 |
| 16-methyl-heptadecanoate (iso) |
326 |
28-methyl-nonacosanoate (iso) |
494 |
| 11-methyl-octadecanoate |
340 |
28-methyl-triacontanoate (anteiso) |
508 |
| 16-methyl-octadecanoate (anteiso) |
340 |
30-methyl-hentriacontanoate (iso) |
522 |
| 18-methyl-nonadecanoate (iso) |
354 |
30-methyl-dotriacontanoate (anteiso) |
536 |
| 18-methyl-eicosanoate (anteiso) |
368 |
32-methyl-tetratriacontanoate (anteiso) |
564 |
| 20-methyl-heneicosanoate (iso) |
382 |
|
|
| |
| 4,8,12-trimethyl-tridecanoate |
298 |
3,7,11,15-tetramethyl-hexadecanoate (phytanate) |
354
|
| |
| 9-tetradecenoate (9-14:1) |
268 |
11-eicosenoate (11-20:1) |
352 |
| 9-hexadecenoate (9-16:1) |
296 |
13-docosenoate (13-22:1) |
380 |
| 9-heptadecenoate (9-17:1) |
310 |
15-tetracosenoate (15-24:1) |
408 |
| 9-octadecenoate (9-18:1) |
324 |
17-hexacosenoate (17-26:1) |
436 |
| 11-octadecenoate (11-18:1) |
324 |
|
|
| |
| 9,12-octadecadienoate (18:2(n-6)) |
322 |
5,9-hexacosadienoate (5,9-26:2) |
434 |
| 9c,11t-octadecadienoate (9,11-18:2) |
322 |
23-methyl-5,9-tetracosadienoate (iso) |
420 |
|
|
24-methyl-5,9-pentacosadienoate (iso) |
434 |
| 5,9-pentacosadienoate (5,9-25:2) |
420 |
|
|
| |
| 6,9,12-hexadecatrienoate (16:3(n-4)) |
292 |
5,9,17-hexacosatrienoate (5,9,17-26:3) |
432 |
| 9,12,15-octadecatrienoate (18:3(n-3)) |
320 |
5,9,19-hexacosatrienoate (5,9,19-26:3) |
432 |
| 5,9,17-tetracosatrienoate (5,9,17-24:3) |
404 |
5,9,19-octacosatrienoate (5,9,19-28:3) |
460 |
| |
| 6,9,12,15-octadecatetraenoate (18:3(n-3)) |
318 |
6,9,12,15,18-heneicosapentaenoate (21:5(n-3)) |
358 |
| 5,8,11,14-eicosatetraenoate (20:4(n-6)) |
346 |
4,7,10,13,16-docosapentaenoate (22:5(n-6)) |
372 |
| 8,11,14,17-eicosatetraenoate (20:4(n-3)) |
346 |
7,10,13,16,19-docosapentaenoate (22:5(n-3)) |
372 |
| 7,10,13,16-docosatetraenoate (22:4(n-6)) |
374 |
4,7,10,13,16,19-docosahexaenoate (22:6(n-3)) |
370 |
| 5,8,11,14,17-eicosapentaenoate (20:5(n-3)) |
344 |
6,9,12,15,18,21-tetracosahexaenoate (24:6(n-3)) |
398 |
| |
| 11,12-methylene-octadecanoate |
338 |
|
|
Butyl esters of fatty acids
|
| Fatty acid |
M+ |
Fatty acid |
M+ |
| |
| hexanoate (6:0) |
172 |
9-octadecenoate (9-18:1) |
338 |
| octanoate (8:0) |
200 |
11-eicosenoate (11-20:1) |
366 |
| decanoate (10:0) |
228 |
13-docosenoate (13-22:1) |
394 |
| dodecanoate (12:0) |
256 |
15-tetracosenoate (15-24:1) |
422 |
| tetradecanoate (14:0) |
284 |
|
|
| pentadecanoate (15:0) |
298 |
9,12-octadecadienoate (18:2(n-6)) |
336 |
| hexadecanoate (16:0) |
312 |
9-cis,11-trans-octadecadienoate |
336 |
| heptadecanoate (17:0) |
326 |
|
|
| octadecanoate (18:0) |
340 |
6,9,12-hexadecatrienoate (16:3(n-4)) |
306 |
| eicosanoate (20:0) |
368 |
9,12,15-octadecatrienoate (18:3(n-3)) |
334 |
| 4,8,12-trimethyltridecanoate |
312 |
6,9,12,15-octadecatetraenoate (18:4(n-3)) |
332 |
| 13-methyltetradecanoate (iso) |
298 |
5,8,11,14-eicosatetraenoate (20:4(n-6)) |
360 |
| 2,6,10,14-tetramethylpentadecanoate |
354 |
8,11,14,17-eicosatetraenoate (20:4(n-3)) |
360 |
| 14-methylhexadecanoate (anteiso) |
326 |
5,8,11,14,17-eicosapentaenoate (20:5(n-3)) |
358 |
| 15-methylhexadecanoate (iso) |
326 |
7,10,13,16,19-docosapentaenoate (22:5(n-3)) |
386 |
|
|
4,7,10,13,16,19-docosahexaenoate (22:6(n-3)) |
384 |
| 9-tetradecenoate (9-14:1) |
282 |
|
|
| 9-hexadecenoate (9-16:1) |
310 |
|
|
Phenacyl esters of fatty acids
|
| Fatty acid |
M+ |
Fatty acid |
M+ |
| |
| hexadecanoate (16:0) |
374 |
9,12-octadecadienoate (18:2(n-6)) |
398 |
| 11-octadecenoate (11-18:1) |
40 |
9,12,15-octadecatrienoate (18:3(n-3)) |
396 |
Trimethylsilyl esters of fatty acids
|
| Fatty acid |
M+ |
Fatty acid |
M+ |
| |
| tetradecanoate (14:0) |
300 |
hexacosanoate (26:0) |
468 |
| hexadecanoate (16:0) |
328 |
hexadecenoate (16:1) |
326 |
| heptadecanoate (17:0) |
342 |
octadec-9-enoate |
354 |
| octadecanoate (18:0) |
356 |
eicosenoate (20:1) |
382 |
| docosanoate (22:0) |
412 |
docosenoate (22:1) |
410 |
| tricosanoate (23:0) |
426 |
tetracosenoate (24:1) |
438 |
| tetracosanoate (24:0) |
440 |
octadec-9,12-dienoate |
352 |
| |
| hexadecane-1,16-dioate |
430 |
octadec-9-ene-1,18-dioate |
456 |
| 15-hydroxy-pentadecanoate (+ TMSE) |
402 |
18-hydroxy-octadec-9-enoate (+ TMSE) |
442 |
| |
| coumaric acid - bisOTMS |
308 |
sinapic acid - bisOTMS |
368 |
| ferulic acid - bisOTMS |
338 |
| |
Wax esters
|
| Wax ester |
M+ |
Wax ester |
M+ |
| |
| tetradecanyl tetradecanoate |
424 |
docosanyl eicosanoate |
620 |
| hexadecanyl tetradecanoate |
452 |
docosanyl docosanoate |
648 |
| tetradecanyl hexadecanoate |
452 |
|
|
| hexadecanyl hexadecanoate |
480 |
octadecanyl hexadecenoate |
506 |
| octadecanyl hexadecanoate |
508 |
eicosanyl octadecenoate |
562 |
| eicosanyl eicosanoate |
592 |
octadecenyl hexadecanoate |
506 |
| |
| octadecyl coumarate - OTMS |
488 |
octadecyl ferulate - OTMS |
518 |
| eicosanyl coumarate - OTMS |
516 |
eicosanyl ferulate - OTMS |
546 |
| docosanyl coumarate - OTMS |
544 |
docosanyl ferulate - OTMS |
574 |
| |
| octadecyl caffeate - OTMS |
576 |
|
|
