DOI: 10.1002/adsc.200606171 Internal Alkene Hydroaminations Catalyzed by Zirconium(IV) Complexes and Asymmetric Alkene Hydroaminations Catalyzed by YttriumACHTUNGTRENNUNG(III) Complexes Hyunseok Kim, a Young Kwan Kim, b Jun Hwan Shim, a Misook Kim, a Mijung Han, a Tom Livinghouse, b, * and Phil Ho Lee a, * a Department of Chemistry, Kangwon National University, Chunchon 200-701, Republic of Korea Fax: (+ 82)-33-253-7582; e-mail: phlee@kangwon.ac.kr b Department of Chemistry, Montana State University, Bozeman, MT 59717, U.S.A. Fax: (+ 1)-406-994-5407; e-mail: livinghouse@chemistry.montana.edu Received: April 10, 2006; Accepted: September 22, 2006 This paper is dedicated to Professor Eun Lee on the occasion of his 60 th birthday. Abstract: The thiophosphinic amide 2 was prepared in 68 % yield by the reaction of 2,2-dimethyl-1,3-pro- panediamine with diisopropylchlorophosphine fol- lowed by the addition of sulfur. Attachment of the proligand 2 to zirconium was achieved by direct met- alation with ZrACHTUNGTRENNUNG(NMe 2 ) 4 in benzene-d 6 or toluene-d 8 to afford complex 3 via elimination of dimethyla- mine. The neutral Zr(IV) complex 3 has been shown to be an effective precatalyst for intramolecular alkene hydroaminations that provide cyclic amines in good to excellent yields. A variety of chiral ligands (20, 22, 24, and 25–30) were prepared for asymmetric internal alkene hydroaminations. Metalation of chiral ligands to yttrium was accomplished with Y[N- ACHTUNGTRENNUNG(TMS) 2 ] 3 in benzene-d 6 or toluene-d 8 to give com- plexes. Treatment of 7 with 5 mol% of 33 in ben- zene-d 6 (25 8C, 18 h) or toluene-d 8 (25 8C, 15 h) af- forded 2,4,4-trimethylpyrrolidine 14 in 95% yield (61% ee). Keywords: asymmetric hydroamination; catalysis; cyclization; yttrium; zirconium Introduction The catalyzed intramolecular hydroamination of al- kenes constitutes a powerful method for the synthesis of nitrogen heterocycles. [1] A variety of novel non- metallocene complexes [2] of group 3 metals as cata- lysts for this reaction has recently been added to the group 3 metallocene catalysts developed by Marks and co-workers. [3] Although there are many reviews that describe both the intra- and intermolecular hy- droamination of alkynes [4a–d] and allenes [4e,f] catalyzed by various complexes of the group 4 metals, there have been only very few reports of intramolecular alkene hydroaminations mediated by complexes of metals belonging to this group. Recently, we commu- nicated Zr-catalyzed intramolecular alkene hydroami- nations, [5] and Schafer and Hultzsch found that Ti- ACHTUNGTRENNUNG(NMe 2 ) 4 [6] and cationic species [7] of the group 4 metals were efficient for alkene hydroaminations. Also, Liv- inghouse has previously reported that chelating bis- (thiophosphinic amidate), “NPS”, complexes of the group 3 metal (yttrium) are potent catalysts for intra- molecular alkene hydroamination. [2i] In this paper, we show that the neutral Zr(IV) bis(thiophosphinic ami- date) complex is an efficient precatalyst for the cycli- zation of representative primary aminoalkenes. Also, the chiral YACHTUNGTRENNUNG(III) bis(thiophosphinic amidate) com- plexes obtained from chiral ligands (20, 22, 24, and 25–30) and Y[NACHTUNGTRENNUNG(TMS) 2 ] 3 were evaluated for the cata- lytic asymmetric intramolecular hydroamination of al- kenes (Scheme 1). Scheme 1. Adv. Synth. Catal. 2006, 348, 2609 – 2618 # 2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim 2609 FULL PAPERS