Effi cient method was developed for thiols aminomethylation using N,N,N′,N′-tetra-methylmethanediamine in the presence of Sm and Fe salts. Aminosulfi des were obtained in high yields and selectivity.Organic compounds containing nitrogen and sulfur are used as effi cient plant protecting substances[1-3], antioxidants, anticorrosion, antiscoring, and antiwear additives to fuels and lubricants [4][5][6][7][8][9][10].Up to now one of the most known methods for the synthesis of aminosulfi des remains the classic Mannich aminomethylation of thiols by secondary amines and aldehydes [11], but this procedure possesses certain limitations. For instance, the thiols aminomethylation using formaldehyde and dimethylamine occurs with relatively low yields [12] due to the application and dosing of the water solutions of the initial reagents. We report here on a new approach to aminomethylation of mono-and dithiols applying an available and industrially produced N,N,N′,N′-tetramethylmethanediamine that exhibits a high reactivity in the catalyzed aminomethylation of terminal acetylenes with the use of gem-diamines [13][14][15].By an example of the reaction of pentylmercaptan with diamine it was established that among the tested catalysts based on halides and complexes of Cu, Sm, Fe, Co, Mn, Pd, V, Zr, Ti the highest activity exhibited SmCl 3 ·6H 2 O and FeCl 3 ·6H 2 O. In the presence of SmCl 3 ·6H 2 O (the ratio [pentylmercaptan] : [diamine] : [Sm] 10 : 12 : 0.5, 60°С, 1.5 h, solvent) in the argon atmosphere N,N-dimethyl-1-(pentylsulfanyl)methanamine (Iа) formed in 98% yield, and in the presence of FeCl 3 ·6H 2 O in analogous conditions, in 95% yield. The use as solvents of benzene and DMF reduced the yield of aminosulfi de Iа to 50%. The yield is fairly sensitive to the nature of the anion at the central atom of the catalyst: SmCl 3 ·6H 2 O (98%), Sm(NO 3 ) 3 ·6H 2 O (60%), Sm(acac) 3 ·H 2 O (43%).Without catalyst under the mentioned conditions aminosulfide Iа formed in the yield not exceeding 40%. In this reaction CoCl 2 , CuCl, CuCl 2 ·2H 2 O, NiCl 2 , MnCl 2 ·2H 2 O, PdCl 2 , ZnCl 2 did not show any considerable catalytic activity.In the developed optimal conditions (5 mol% SmCl 3 ·6H 2 O, 60°С, 1.5 h, CHCl 3 ) the aminomethylation of butyl-, heptyl-, isopropyl-, tert-butyl-, phenyl-, benzyl-, 1,3-benzothiazol-2-yl-, 1,3-benzoxazol-2-ylthiols with the help of the diamine (molar ratio thiol-diamine 10 : 12) resulted in corresponding aminosulfi des Ib-Ii in 84-98% yields.