Abstract
A domino 1,4-addition/alkyne carbozincation sequence based
on a radical zinc-atom transfer process is disclosed. Two efficient
multicomponent approaches to 3-alkylidenetetrahydrofurans from β-(propargyloxy)enoates
bearing pendant alkynes (including ynamides) have been established:
one involving the direct addition of dialkylzincs, and the second
involving the dimethylzinc-mediated addition of alkyl iodides. Both
sequences utilize the stereoselective formation of intermediate
alkylidenezincs well suited for in situ functionalization
with electrophiles.
1 Introduction
2 1,4-Addition/Cyclization of Dialkylzincs on β-(Propargyloxy)enoates
2.1 β-(Propargyloxy)enoates with a Pendant Terminal
Alkyne
2.2 β-(Propargyloxy)enoates with a Pendant Substituted Alkyne
2.3 β-(Propargyloxy)enoates with a Pendant Ynamide
3 1,4-Addition/Cyclization of Alkylzinc Halides on β-(Propargyloxy)enoates
4 Dialkylzinc-Mediated 1,4-Addition/Cyclization of
Alkyl Iodides on β-(Propargyloxy)enoates
5 Conclusion; Current and Future Work
Key words
zinc - radicals - tandem reaction - alkynes - metalation
References
Reviews:
<A NAME="RZ55710SS-1A">1a</A>
Bazin S.
Feray L.
Bertrand MP.
Chimia
2006,
60:
260
<A NAME="RZ55710SS-1B">1b</A>
Akindele T.
Yamada K.-i.
Tomioka K.
Acc.
Chem. Res.
2009,
42:
345
<A NAME="RZ55710SS-2">2</A> Historical account, see:
Seyferth D.
Organometallics
2001,
20:
2940
<A NAME="RZ55710SS-3A">3a</A>
Lewinski J.
Marciniac W.
Lipkowski J.
Justyniak I.
J.
Am. Chem. Soc.
2003,
125:
12698
<A NAME="RZ55710SS-3B">3b</A>
Lewinski J.
Sliwinski W.
Dranka M.
Justyniak I.
Lipkowski J.
Angew.
Chem. Int. Ed.
2006,
45:
4826
<A NAME="RZ55710SS-3C">3c</A>
Lewinski J.
Suwala K.
Kubisiak M.
Ochal Z.
Justyniak I.
Lipkowski J.
Angew. Chem. Int. Ed.
2008,
47:
7888
<A NAME="RZ55710SS-3D">3d</A>
Lewinski J.
Bury W.
Dutkiewicz M.
Maurin M.
Justyniak I.
Lipkowski J.
Angew. Chem. Int. Ed.
2008,
47:
573
<A NAME="RZ55710SS-3E">3e</A>
Lewinski J.
Koscielski M.
Suwala K.
Justyniak I.
Angew. Chem. Int. Ed.
2009,
48:
7017
<A NAME="RZ55710SS-3F">3f</A>
Lewinski J.
Suwala K.
Kaczorowski T.
Galezowski M.
Gryko DT.
Justyniak I.
Lipkowski J.
Chem.
Commun.
2009,
215
<A NAME="RZ55710SS-4">4</A>
Jana S.
Berger RJF.
Fröhlich R.
Pape T.
Mitzel NW.
Inorg.
Chem.
2007,
46:
4293
<A NAME="RZ55710SS-5">5</A>
Mileo E.
Benfatti F.
Cozzi PG.
Lucarini M.
Chem. Commun.
2009,
469
<A NAME="RZ55710SS-6">6</A>
Maury J.
Feray L.
Bazin S.
Clément J.-L.
Marque SRA.
Siri D.
Bertrand MP.
Chem.
Eur. J.
2011,
17:
1586
<A NAME="RZ55710SS-7">7</A>
Davies AG.
Roberts BP.
Acc. Chem. Res.
1972,
387 ; and references cited therein
<A NAME="RZ55710SS-8">8</A> For the first use of Et2Zn
as radical mediator in the presence of oxygen in the context of
synthesis, see:
Ryu I.
Araki F.
Minakata S.
Komatsu M.
Tetrahedron
Lett.
1998,
39:
6335
<A NAME="RZ55710SS-9">9</A>
Cohen T.
Gibney H.
Ivanov R.
Yeh EA.-H.
Marek I.
Curran DP.
J. Am. Chem. Soc.
2007,
129:
15405
<A NAME="RZ55710SS-10A">10a</A>
Bertrand MP.
Feray L.
Nouguier R.
Perfetti P.
J.
Org. Chem.
1999,
64:
9189
<A NAME="RZ55710SS-10B">10b</A>
Bazin S.
Feray L.
Siri D.
Naubron J.-V.
Bertrand MP.
Chem.
Commun.
2002,
2506
<A NAME="RZ55710SS-10C">10c</A>
Bazin S.
Feray L.
Vanthuyne N.
Bertrand MP.
Tetrahedron
2005,
61:
4261
<A NAME="RZ55710SS-10D">10d</A>
Bazin S.
Feray L.
Vanthuyne N.
Siri D.
Bertrand MP.
Tetrahedron
2007,
63:
77
<A NAME="RZ55710SS-10E">10e</A>
Maury J.
Feray L.
Perfetti P.
Bertrand MP.
Org. Lett.
2010,
12:
3590
<A NAME="RZ55710SS-11">11</A>
Van der Deen H.
Kellog RM.
Feringa BL.
Org. Lett.
2000,
2:
1593
<A NAME="RZ55710SS-12A">12a</A>
Miyabe H.
Asada R.
Yoshida K.
Takemoto Y.
Synlett
2004,
540
<A NAME="RZ55710SS-12B">12b</A>
Miyabe H.
Asada R.
Takemoto Y.
Tetrahedron
2005,
61:
385
<A NAME="RZ55710SS-13">13</A>
Yamada K.-i.
Umeki M.
Maekawa M.
Yamamoto Y.
Akindele Y.
Nakano M.
Tomioka K.
Tetrahedron
2008,
64:
7258
<A NAME="RZ55710SS-14A">14a</A>
Cozzi PG.
Angew. Chem. Int. Ed.
2006,
45:
2951
<A NAME="RZ55710SS-14B">14b</A>
Cozzi PG.
Adv. Synth. Catal.
2006,
348:
2075
<A NAME="RZ55710SS-14C">14c</A>
Cozzi PG.
Mignogna A.
Vicennati P.
Adv. Synth. Catal.
2008,
350:
975
<A NAME="RZ55710SS-14D">14d</A>
Fernández-Ibañez MA.
Maciá B.
Minnaard AJ.
Feringa BL.
Angew. Chem. Int. Ed.
2008,
47:
1317
<A NAME="RZ55710SS-14E">14e</A>
Cozzi PG.
Benfatti F.
Guiteras Capdevila M.
Mignogna A.
Chem. Commun.
2008,
3317
Furthermore, it has been proposed
that transition-metal-promoted zinc/iodine exchange involves
a radical mechanism, Cu(I):
<A NAME="RZ55710SS-15A">15a</A>
Rozema MJ.
AchyuthaRao S.
Knochel P.
J. Org. Chem.
1992,
57:
1956
Pd(0):
<A NAME="RZ55710SS-15B">15b</A>
Stadtmüller H.
Vaupel A.
Tucker CE.
Stüdemann T.
Knochel P.
Chem. Eur. J.
1996,
2:
1204
<A NAME="RZ55710SS-15C">15c</A>
Stadtmüller H.
Lentz R.
Tucker C.
Stüdemann T.
Dörner W.
Knochel P.
J. Am. Chem.
Soc.
1993,
115:
7027
Ni(0):
<A NAME="RZ55710SS-15D">15d</A>
Vaupel A.
Knochel P.
Tetrahedron Lett.
1994,
35:
8349
<A NAME="RZ55710SS-15E">15e</A>
Vaupel A.
Knochel P.
J. Org. Chem.
1996,
61:
5743
Mn(II)/Cu(I):
<A NAME="RZ55710SS-15F">15f</A>
Riguet E.
Klement I.
Kishan Reddy Ch.
Cahiez G.
Knochel P.
Tetrahedron Lett.
1996,
37:
5865
<A NAME="RZ55710SS-16A">16a</A>
Denes F.
Chemla F.
Normant J.-F.
Angew. Chem. Int. Ed.
2003,
42:
4043
<A NAME="RZ55710SS-16B">16b</A>
Denes F.
Pérez-Luna A.
Cutri S.
Chemla F.
Chem. Eur. J.
2006,
12:
6506
<A NAME="RZ55710SS-16C">16c</A>
Denes F.
Pérez-Luna A.
Chemla F.
J.
Org. Chem.
2007,
72:
398
<A NAME="RZ55710SS-16D">16d</A>
Giboulot S.
Pérez-Luna A.
Botuha C.
Ferreira F.
Chemla F.
Tetrahedron
Lett.
2008,
49:
3963
<A NAME="RZ55710SS-17">17</A>
Feray L.
Bertrand MP.
Eur. J. Org. Chem.
2008,
3164
<A NAME="RZ55710SS-18">18</A> For a related photoinduced reaction,
see:
Charette AB.
Beauchemin A.
Marcoux J.-F.
J. Am.
Chem. Soc.
1998,
120:
5114
For important studies on radical
formation by SET from dialkylzinc coordination complexes, see:
<A NAME="RZ55710SS-19A">19a</A>
Wissing E.
Rijnberg E.
van der Schaaf PA.
van Gorp K.
Boersma J.
van Koten G.
Organometallics
1994,
13:
2609
<A NAME="RZ55710SS-19B">19b</A>
Wissing E.
van der Linden S.
Rijnberg E.
Boersma J.
Smeets WJJ.
Spek AL.
van Koten G.
Organometallics
1994,
13:
2602 ; and references cited therein
<A NAME="RZ55710SS-20">20</A>
Chen Z.
Zhang Y.-X.
An Y.
Song X.-L.
Wang Y.-H.
Zhu L.-L.
Guo L.
Eur. J. Org.
Chem.
2009,
5146
<A NAME="RZ55710SS-21">21</A>
Reductive zincation of a vinyl radical
has also been suggested to account for the formation of allenoates following
zinc-mediated radical addition to propiolates, see ref. 17.
<A NAME="RZ55710SS-22">22</A> Vinylcyclopentyl zinc has been prepared
by reductive cyclization:
Crandall JK.
Ayers TA.
Organometallics
1992,
11:
473
<A NAME="RZ55710SS-23">23</A> Ni(II)-catalyzed intermolecular
carbozincation, see:
Stüdemann T.
Knochel P.
Angew. Chem. Int. Ed.
1997,
36:
93
<A NAME="RZ55710SS-24">24</A>
Pérez-Luna A.
Botuha C.
Ferreira F.
Chemla F.
Chem. Eur. J.
2008,
14:
8784
Selected examples:
<A NAME="RZ55710SS-25A">25a</A>
Bertrand MT.
Courtois G.
Migniniac L.
Tetrahedron Lett.
1974,
15:
3147
<A NAME="RZ55710SS-25B">25b</A>
Nakamura M.
Fujimoto T.
Endo K.
Nakamura E.
Org. Lett.
2004,
6:
4837
<A NAME="RZ55710SS-25C">25c</A>
Cantagrel F.
Pinet S.
Gimbert Y.
Chavant PY.
Eur. J. Org. Chem.
2005,
2694
<A NAME="RZ55710SS-26">26</A>
See the supporting information in
ref. 24.
Deprotonation of 1a responsible
for the formation of 10 could also be effected
by Bu2Zn, even though deprotonation of terminal alkynes
by dialkylzincs in the absence of ligands is not a fast process,
see:
<A NAME="RZ55710SS-27A">27a</A>
Okhlobystin OY.
Zakharkin LI.
J.
Organomet. Chem.
1965,
3:
257
<A NAME="RZ55710SS-27B">27b</A>
De Koning AJ.
Van Rijn PE.
Boersma J.
Van der Kerk GJM.
J. Organomet.
Chem.
1979,
174:
129
<A NAME="RZ55710SS-27C">27c</A>
Pinet S.
Pandya SU.
Chavant PY.
Ayling A.
Vallée Y.
Org. Lett.
2002,
4:
1463
<A NAME="RZ55710SS-28">28</A>
Cote A.
Charette AB.
J. Am. Chem. Soc.
2008,
130:
2771
<A NAME="RZ55710SS-29">29</A>
Haaland A.
Green JC.
McGrady GS.
Downs AJ.
Gullo E.
Lyall MJ.
Timberlake J.
Tutukin AV.
Volden HV.
Ostby K.-A.
Dalton
Trans.
2003,
4356
<A NAME="RZ55710SS-30">30</A>
Bamford CH.
Newitt DM.
J. Chem. Soc., Abstr.
1946,
688
<A NAME="RZ55710SS-31">31</A>
When CH2Cl2 was
used as solvent, the Z/E ratio of product 5ha might
not fully represent the diastereoselectivity of the zinc-atom transfer
since in addition to these two diastereomers, a third tetrahydrofuran
side product having incorporated a butyl residue was detected (∼20% yield
in the crude) but could not be fully identified. In any case the diastereoselectivity
of the reaction between 1h and Bu2Zn
in CH2Cl2 should at best be mediocre.
<A NAME="RZ55710SS-32">32</A>
Guijarro A. In
The Chemistry of Organozinc Compounds
Rappoport Z.
Marek I.
Wiley;
Chichester:
2007.
p.193-236
<A NAME="RZ55710SS-33">33</A>
Jourmet M.
Malacria M.
J. Org. Chem.
1992,
57:
3085
<A NAME="RZ55710SS-34">34</A>
Curran DP.
Chen M.-H.
Kim DJ.
J.
Am. Chem. Soc.
1989,
111:
6265
Even though α-silyl stabilization
of vinyl radicals leads to a tendency towards linearization:
<A NAME="RZ55710SS-35A">35a</A>
Lalitha S.
Chandrasekhar J.
Proc.-Indian
Acad. Sci., Chem. Sci.
1994,
106:
259 ;
they are better represented as very rapidly Z/E interconverting bent radicals:
<A NAME="RZ55710SS-35B">35b</A>
Rubin H.
Fischer H.
Helv. Chim. Acta
1996,
79:
1670
<A NAME="RZ55710SS-35C">35c</A>
Bucher G.
Mahajan AA.
Schmittel M.
J.
Org. Chem.
2009,
74:
5850
<A NAME="RZ55710SS-36A">36a</A>
Chechik-Lankin H.
Livshin S.
Marek I.
Synlett
2005,
2098
<A NAME="RZ55710SS-36B">36b</A>
Prakash Das J.
Chechik H.
Marek I.
Nature Chem.
2009,
1:
128
<A NAME="RZ55710SS-37A">37a</A>
Gourdet B.
Lam HW.
J.
Am. Chem. Soc.
2009,
131:
3802
<A NAME="RZ55710SS-37B">37b</A>
Gourdet B.
Rudkin ME.
Watts CA.
Lam HW.
J.
Org. Chem.
2009,
74:
7849
<A NAME="RZ55710SS-38A">38a</A>
Yasui H.
Yorimitsu H.
Oshima K.
Chem. Lett.
2007,
36:
32
<A NAME="RZ55710SS-38B">38b</A>
Yasui H.
Yorimitsu H.
Oshima K.
Bull.
Chem. Soc. Jpn.
2008,
81:
373
<A NAME="RZ55710SS-39">39</A>
Marion F.
Courillon C.
Malacria M.
Org.
Lett.
2003,
5:
5095
<A NAME="RZ55710SS-40A">40a</A>
Sato A.
Yorimitsu H.
Oshima K.
Synlett
2009,
28
<A NAME="RZ55710SS-40B">40b</A>
Sato A.
Yorimitsu H.
Oshima K.
Bull.
Korean Chem. Soc.
2010,
31:
570
<A NAME="RZ55710SS-41">41</A>
Banerjee B.
Litvinov DN.
Kang J.
Bettale JD.
Castle SL.
Org. Lett.
2010,
12:
2650
<A NAME="RZ55710SS-42">42</A>
See the Supporting Information.
<A NAME="RZ55710SS-43A">43a</A>
The Chemistry of Organozinc Compounds
Rappoport Z.
Marek I.
Wiley;
Chichester:
2007.
<A NAME="RZ55710SS-43B">43b</A>
Knochel P.
Millot N.
Rodrigues AL.
Org.
React.
2001,
58:
417
<A NAME="RZ55710SS-44">44</A>
Blake AJ.
Shannon J.
Stephens JC.
Woodward S.
Chem. Eur. J.
2007,
13:
2462
<A NAME="RZ55710SS-45">45</A>
Beckwith ALJ.
Tetrahedron
1981,
37:
3073
<A NAME="RZ55710SS-46A">46a</A>
Bertrand MP.
Feray L.
Nouguier R.
Perfetti P.
Synlett
1999,
1148
<A NAME="RZ55710SS-46B">46b</A>
Bertrand MP.
Coantic S.
Feray L.
Nouguier R.
Perfetti P.
Tetrahedron
2000,
56:
3951
<A NAME="RZ55710SS-47A">47a</A>
Miyabe H.
Ushiro C.
Ueda M.
Yamakawa K.
Naito T.
J. Org. Chem.
2000,
65:
176
<A NAME="RZ55710SS-47B">47b</A>
Miyabe H.
Konishi C.
Naito T.
Org.
Lett.
2000,
2:
1443
<A NAME="RZ55710SS-48A">48a</A>
Yamada K.-i.
Yamamoto Y.
Maekawa M.
Akindele T.
Umeki H.
Tomioka K.
Org.
Lett.
2006,
8:
87
<A NAME="RZ55710SS-48B">48b</A>
Yamada K.-i.
Nakano Y.
Maekawa M.
Akindele T.
Tomioka K.
Org.
Lett.
2008,
10:
3805
<A NAME="RZ55710SS-49A">49a</A>
Vleeschouwer FD.
Van Speybroeck V.
Waroquier M.
Geerlings P.
De Proft F.
Org.
Lett.
2007,
9:
2721
<A NAME="RZ55710SS-49B">49b</A>
Fischer H.
Radom L.
Angew. Chem. Int. Ed.
2001,
40:
1340
<A NAME="RZ55710SS-50">50</A> Similar stereoselectivities have
been reported for other related iodine-atom transfer radical cascades,
see for example:
Miyabe H.
Asada R.
Toyoda A.
Takemoto Y.
Angew. Chem. Int. Ed.
2006,
45:
5863
See,
<A NAME="RZ55710SS-51A">51a</A>
Chinkov N.
Tene D.
Marek I. In Metal-Catalyzed Cross Coupling Reactions
2nd
ed.:
Diederich D.
de Meijere A.
Wiley-VCH;
New York:
2004.
p.395
<A NAME="RZ55710SS-51B">51b</A>
Denès F.
Pérez-Luna A.
Chemla F.
Chem. Rev.
2010,
110:
2366
