Subscribe to RSS
DOI: 10.1055/s-0029-1219362
Enantioselective One-Pot Rhodium-Catalyzed Cycloisomerization-Wittig Sequence to Chiral Functionalized 4-Alkyl 3-Alkylidene Tetrahydrofuran(on)es
Publication History
Publication Date:
08 February 2010 (online)
![](https://www.thieme-connect.de/media/synlett/201005/lookinside/thumbnails/10.1055-s-0029-1219362-1.jpg)
Abstract
Alkyl and (hetero)aryl alkyne allyl alcohols can readily be transformed into chiral 4-alkyl 3-alkylidene tetrahydrofurans and tetrahydrofuranones bearing α,β-unsaturated carbonyl side chains in a one-pot fashion via an enantioselective rhodium-catalyzed cycloisomerization-Wittig olefination sequence in good yields (54-86%).
Key words
alkynes - catalysis - cyclization - rhodium - Wittig reactions
- For representative transition-metal-catalyzed cycloisomerization reactions, see the following. Pd:
-
1a
Trost BM. Acc. Chem. Res. 1990, 23: 34 -
1b
Trost BM. Janssen Chim. Acta 1991, 9: 3 -
1c
Trost BM.Krische MJ. Synlett 1998, 1 - Ru:
-
1d
Trost BM. Chem. Ber. 1996, 129: 1313 -
1e
Trost BM.Toste FD. Tetrahedron Lett. 1999, 40: 7739 - Ir:
-
1f
Chatani N.Inoue H.Morimoto T.Muto T.Murai S. J. Org. Chem. 2001, 66: 4433 -
1g
Kezuka S.Okado T.Niou E.Takeuchi R. Org. Lett. 2005, 7: 1711 - Ti:
-
1h
Sturla SJ.Kablaoui NM.Buchwald SL. J. Am. Chem. Soc. 1999, 121: 1976 - Review:
-
1i
Aubert C.Buisine O.Malacria M. Chem. Rev. 2002, 102: 813 - Pd-catalyzed sequences:
-
2a
Kressierer CJ.Müller TJJ. Tetrahedron Lett. 2004, 45: 2155 -
2b
Kressierer CJ.Müller TJJ. Synlett 2005, 1721 -
2c
Kressierer CJ.Müller TJJ. Org. Lett. 2005, 7: 2237 - Ir-catalyzed sequence:
-
2d
Kummeter M.Ruff CM.Müller TJJ. Synlett 2007, 717 - 3
Kressierer CJ.Müller TJJ. Synlett 2004, 655 - 4
Brummond K.McCabe JM. In Modern Rhodium-Catalyzed Organic Reactions 1st ed.:Evans PA. Wiley-VCH; Weinheim: 2005. p.151-171 -
5a
Cao P.Wang B.Zhang X. J. Am. Chem. Soc. 2000, 122: 6490 -
5b
Cao P.Zhang X. Angew. Chem. Int. Ed. 2000, 22: 4104 -
6a
Lei A.He M.Wu S.Zhang X. Angew. Chem. Int. Ed. 2002, 41: 3457 -
6b
Lei A.Waldkirch JP.He M.Zhang X. Angew. Chem. Int. Ed. 2002, 41: 4526 -
6c
Lei A.He M.Zhang X. J. Am. Chem. Soc. 2002, 124: 8198 -
6d
Lei A.He M.Zhang X. Tetrahedron Lett. 2005, 46: 1823 - 7
Hashmi ASK.Haufe P.Rivas Nass A. Adv. Synth. Catal. 2003, 345: 1237 -
8a
Hashmi ASK.Haufe P.Rivas Nass A.Bats JW. Adv. Synth. Catal. 2004, 346: 421 -
8b
Hashmi ASK.Karch R.Rivas Nass A. Chemistry Today 2006, 24: 16 ; supplement - 9
Lei A.He M.Zhang X. J. Am. Chem. Soc. 2003, 125: 11472 - 10
Körber N.Müller TJJ. Chimica Oggi/Chemistry Today 2006, 24: 22 - 11
Körber N.Rominger F.Müller TJJ. Adv. Synth. Catal. 2009, 351: 2921
References and Notes
Typical Procedure
(4h, Table 1, Entry 8)
Under argon atmosphere [RhCl(cod)]2 precursor
(12.3 mg, 0.025 mmol) and (R)-BINAP ligand
(31.1 mg, 0.05 mmol) were placed in a Schlenk tube. Then dried,
degassed DCE
(4 mL) was added, and the solution was stirred
for several minutes, until a dark red solution was formed. Then
alkyne allyl alcohol 1d (218 mg 1.0 mmol)
was added, the solution stirred for another minute, and finally
the reaction was started by addition of AgBF4 solution
(1 mL, 0.05 mmol,
c 0.05 M,
dissolved in DCE). The reaction was monitored by TLC and full conversion
was observed after 5 min at r.t. Then ylide 3b (435
mg, 1.3 equiv, 1.3 mmol) was added. Again the reaction was monitored
by TLC and full conver-sion was observed after 30 min at r.t. The
mixture was poured into Et2O (100 mL), filtered, and
the solvents were removed in vacuo. The residual crude product was
chroma-tographed on silica gel (n-hexane-Et2O = 1:2; R
f
= 0.51)
to give the analytically pure product 4h in
form of a yellow solid (193 mg, 0.71 mmol, 71%); mp 57 ˚C. ¹H
NMR (300 MHz, CDCl3): δ = 2.34 (s,
3 H), 2.37-2.46 (m, 1 H), 2.52-2.62 (m, 1 H),
2.91-3.01 (m, 1 H), 3.60 (dd,
²
J = 8.7 Hz,
³
J = 5.3
Hz, 1 H), 3.73 (s, 3 H), 3.95 (dd,
²
J = 8.7 Hz,
³
J = 6.5
Hz, 1 H), 4.61-4.63 (m, 2 H), 5.90 (dt,
³
J = 15.6
Hz,
³
J = 1.5 Hz,
1 H), 6.33 (dd,
³
J = 4.1 Hz,
³
J = 2.1
Hz, 1 H), 6.93-7.03 (m, 3 H), 7.15 (d,
³
J = 8.0
Hz, 2 H). ¹³C NMR (75.5 MHz, CDCl3): δ = 21.0
(CH3), 35.9 (CH2), 44.2 (CH), 51.4 (CH3),
70.1 (CH2), 71.8 (CH2), 121.3 (CH), 122.7
(CH), 127.8 (CH), 129.2 (CH), 134.1 (Cquat), 136. 5 (Cquat),
142.6 (Cquat), 146.3 (CH), 166.6 (Cquat).
IR (KBr pellet): ν = 3430 (br), 2944 (s), 2865
(m), 1718 (s), 1660 (s), 1513 (s), 1431 (m), 1343 (m), 1313 (m),
1296 (m), 1286 (m), 1221 (m), 1203 (m), 1163 (w), 1063 (s), 1041
(m), 979 (m), 935 (m), 880 (w), 810 (m), 521 (s) cm-¹.
UV/Vis (CH2Cl2): λmax (ε) = 262
(20400), 272 nm(14800). MS (EI): m/z (%) = 272
(15) [M]+, 174 (14), 173 (100) [C12H13O]+,
145 (86) [C10H9O]+, 143
(14), 131 (19), 129 (23) [C10H9]+,
128 (17), 115 (11) [C8H8]+,
105 (38) [C8H9]+,
91 (7) [C7H7]+.
HRMS: m/z calcd for C17H20O3:
272.1412; found: 272.1399. Anal. Calcd (%) for C17H20O3 (272.14):
C, 74.97; H, 7.40. Found: C, 74.94; H, 7.42. (R)-Enantiomer: [α]D
²0 +9.3
(c 4.0 mg/mL, CHCl3). Chiral
HPLC: n-hexane-2-PrOH (95:5),
0.8 mL/min, 272 nm, t
R(major) = 17.1
min, t
R(minor) = 18.2
min; ee > 99%.
CCDC 756431 (4e)
and CCDC 756432 (4h) contain the supplementary
crystallographic data for this paper.
These data can be
obtained free of charge via http://www.ccdc.cam.ac.uk/conts/retrieving.html [or
from the Cambridge Crystallographic Data Center, 12 Union Road, Cambridge
CB2 1EZ, UK; fax:+44 (1223)336033; or deposit@ccdc.cam.ac.uk].