β-Aminoselenenation of alkenes with arylselenenamides in the presence of sulfamic acid

In the present study, we suggested a new method of the synthesis of β aminoalkyl aryl selenides by the reaction of electrophilic selenenation of alkenes with phenylselen enamide 1 in the presence of HOSO2NH2. We have shown earlier that the reaction of arylselenen amides with unsaturated compounds in the presence of phosphorus(V) or sulfur(IV) oxohalides results in the cor responding β halogenalkyl aryl selenides in high yields.1,2 Also, the possibility of a reaction of arylsulfenamides with olefins in the presence of sulfamic acid resulting in substi tuted aminoalkyl aryl sulfides was found.3 It is of note that the Gabriel reaction of nucleophilic substitution of the amino group for halogen successfully used for the preparation of β aminoalkyl sulfides4 is inap plicable in the case of selenium containing analogs. The other known method for obtaining β aminoalkyl aryl se lenides (in the form of NBoc derivatives)5 with olefins as the starting compounds requires preliminary aziridination of the alkenes, the use of indium iodide, and the inert atmosphere. We used cyclohexene and hex 1 ene in our experi ments. The reaction of phenylselenenamide 1 (see Ref. 3) with hex 1 ene occurs regioselectively with the formation of 2 amino 1 phenylselenohexane (2). trans Amino se lenide 3 was obtained from cyclohexene (Scheme 1). The structures of the obtained products were estab lished by 1H and 13C NMR spectroscopy. In the 1H NMR spectrum of amino selenide 2, a half width of the signals for the protons HCSe and HCN is ∼25 Hz, which unam biguously indicated trans diequatorial orientation of the substituents and the axial positions of the corresponding protons of the cyclohexane moiety. In the two dimen sional correlation spectrum 13C—1H HMBC of compound 3, intense cross peaks corresponding to the C(1 )—Ha(1) and C(1 )—Hb(1) ( 3J) couplings are present. Besides, in the 13C NMR spectrum of amino selenide 3 satellite peaks were observed corresponding to the 77Se and 13C coupling with J = 65 Hz. Thus, we suggested a convenient method for the syn thesis of primary alkylamines containing arylseleno group in the β position.