Abstract
A highly active catalyst for the Buchwald-Hartwig amination has been developed. The new catalyst, a combination of a dimethylaminomethyl ferrocene palladacycle and bis(2-norbornyl)phosphine shows high activity and broad scope for the coupling of non- or deactivated aryl chlorides with primary and secondary amines as well as (hindered) anilines.
Key words
Buchwald-Hartwig amination - aryl chloride - Pd catalysis - palladacycle - secondary phosphine - SK-CC02-A
References
1a
Tsuji J.
Palladium Reagents and Catalysts
John Wiley and Sons Ltd.;
Chichester:
1995.
1b
Metal-Catalyzed Cross-Coupling Reactions
Diederich F.
Stang PJ.
Wiley-VCH;
Weinheim:
1998.
1c
Stark G.
Riermeier TH.
Beller M. In Transition Metals for Organic Synthesis
Vol. 1:
Beller M.
Bolm C.
Wiley-VCH;
Weinheim:
1998.
p.208
2
Schiedel M.-S.
Briehn CA.
Bäuerle R.
J. Organomet. Chem.
2002,
653:
200
3a
Zapf A.
Beller M.
Top. Catal.
2002,
19:
101
3b
Prashad M.
Hu B.
Har D.
Repic O.
Blacklock TJ.
Acemoglu M.
Adv. Synth. Catal.
2001,
343:
461
Pd-phosphine catalysts:
4a
Zim D.
Buchwald SL.
Org. Lett.
2003,
5:
2413
4b
Wolfe JP.
Tomori H.
Sadighi JP.
Yin J.
Buchwald SL.
J. Org. Chem.
2000,
65:
1158
4c
Kuwano R.
Utsunomiya M.
Hartwig JF.
J. Org. Chem.
2002,
67:
6479
4d
Stambuli JP.
Kuwano R.
Hartwig JF.
Angew. Chem. Int. Ed.
2002,
41:
4746
4e
Schnyder A.
Indolese AF.
Studer M.
Blaser HU.
Angew. Chem. Int. Ed.
2002,
41:
3668
4f
Bedford RB.
Blake ME.
Adv. Synth. Catal.
2003,
345:
1107
4g
Dura-Vila V.
Mingos KMP.
Vilar R.
White AJP.
Williams DJ.
J. Organomet. Chem.
2000,
600:
198
Pd-carbene catalysts:
5a
Viciu MS.
Kissling RM.
Stevens ED.
Nolan SP.
Org. Lett.
2002,
4:
229
5b
Viciu MS.
Kelly RA.
Stevens ED.
Naud F.
Studer M.
Nolan SP.
Org. Lett.
2003,
5:
1479
5c
Selvakumar K.
Zapf A.
Spannenberg A.
Beller M.
Chem.-Eur. J.
2002,
8:
3901
6
Schnyder A.
Aemmer T.
Indolese AF.
Pittelkow U.
Studer M.
Adv. Synth. Catal.
2002,
344:
495
7 Available from Strem and Fluka or in technical quantities from Solvias.
8 For a related single-component catalyst see ref. 4d.
9a
Lopez C.
Bosque R.
Solans X.
Font-Bardia M.
J. Organomet. Chem.
1997,
539:
99
9b
Beletskaya IP.
Kashin AN.
Karlstedt NB.
Mitin AV.
Cheprakov AV.
Kazankov GM.
J. Organomet. Chem.
2001,
622:
89
9c
Albisson DA.
Bedford RB.
Lawrence SE.
Scully PN.
Chem. Commun.
1998,
2095
9d
Gaunt JC.
Shaw BL.
J. Organomet. Chem.
1975,
102:
511
10
Blaser HU.
Brieden W.
Pugin B.
Spindler F.
Studer M.
Togni A.
Top. Catal.
2002,
19:
3
11
Typical Procedure: The catalysts were prepared by mixing the secondary phosphine with the Pd precursor (1:1 ratio) in dioxane at r.t. for 30 min. Then, 1 mmol Ar-Cl and 1.2 mmol amine were added to the reaction tubes containing 2.5 mL dioxane 1.4 mmol NaOt-Bu and dodecane (internal standard). The mixture was heated to 80 °C, 0.5 mL catalyst solution (0.005 mmol Pd) was added and then heated further to 110 °C where the reaction was performed. After 2 h samples were taken and analyzed by GC.
12
Marcoux JF.
Wagaw S.
Buchwald SL.
J. Org. Chem.
1997,
62:
1568
13
Roy AH.
Hartwig JF.
J. Am. Chem. Soc.
2003,
125:
8704
14
Hayashi T.
Mise T.
Fukushima M.
Kagotani M.
Nagashima N.
Hamada Y.
Matsumoto A.
Kawakami S.
Konishi M.
Yamamoto K.
Kumada M.
Bull. Chem. Soc. Jpn.
1980,
53:
1138
15 For detailed comparisons see: product P2, ref. 4c,4d; product P3, ref. 5b; product P4, ref. 4a, 5b; product P5, ref. 5a; product P8, ref. 4a, 4c, 4d, 5a.
16 The single experiments were performed on a 1 mmol scale in analogy to ref. 12.
