Methyldodecanoate

Acenapthene (99%), benzophenone (ReagentPlus^®, 99%), cuminaldehyd (≥98%), dimethylphthalate (≥99%), and methyldodecanoate (≥99.5%), as substances for the evaluation of the ion source parameters, were purchased from Sigma-Aldrich (Steinheim, Germany). A multicompound solution (MIX-1) was prepared in methanol (LC-MS Grade) from T. Baker (Giwice, Poland) in a concentration range from 0.1 to 1000 µg/L.
A multiresidue pesticide kit (cat 32562) was purchased from Restek GmbH (Bad Homburg, Germany). It contains organophosphorus (OPP: cat 32563, 32570, 32571), organonitrogen (ONP: cat 32565, 32566, 32567), synthetic pyrethroide (SPP: cat 32568) compounds and herbicide methyl esters (HME: Cat 32569) in toluene (each 100 µg/mL). A multicompound solution of organophosphorus and organonitrogen was prepared. All pesticides were diluted with toluene to a final concentration between 0.1 and 1000 µg/L. Nitrogen and Helium 99.999% were obtained from Air Liquide (Duesseldorf, Germany).

The following compounds were used as authentic standards in the GC-MS and GC-FID assays. Ethyl propanoate (99% purity), 2,3-butanediol isomers (98%), ethyl 2-methylpropanoate (≥ 98%), ethyl 2-methylbutanoate (≥ 98%), n-propyl 2-methylpropanoate (≥ 97%), 4-heptanone (98%), 2-ethyl-1-hexanol (≥ 99.6%), diethyl succinate (99%), 2-bornanone (≥ 97%), methyl dodecanoate (≥ 98%), ethyl dodecanoate (≥ 98%), methyl tetradecanoate (≥ 98%), ethyl tetradecanoate (99%), ethyl (Z)-9-tetradecenoate (97%), ethyl hexadecanoate (≥ 99%), ethyl (Z)-9-octadecenoate (98%) and n-hexane (≥ 97%) were procured from Sigma-Aldrich (St. Louis, MO, USA). Ethyl (Z)-9-hexadecenoate and ethyl (E)-9-octadecenoate, N-(2-methylbutyl)acetamide, N-(3-methylbutyl)acetamide, N-(2-methylbutyl)propanamide, N-(3-methylbutyl)propanamide, N-(2-methylbutyl)-2-methylpropanamide and N-(3-methylbutyl)-2-methylpropanamide, all at ≥ 98.0% purity (by GC), were synthesised previously [53 (link), 55 (link)].