Regioselective and Stereospecific Formation of 2-Ethynyl3ghyd~x~~ra~yd~py~a~ Derivatives via d-End0 Ring Closure
1
M = CO2(CO)6
2 @is)
3 (rrans)
Table. Ring Closurea of Cobalt Complexed Acetylcnic Epoxides
1
mm-la
H
2a:3a
(%:4)
65
2
Pans-lbd
TMS
2b : 3b
(91 : 9)
86
3
#WIS-IC
BU”
2c:3c
(97:3)
97
4
maM-ld
2d:3d
(99:1)
%
w-v
5
uanvle 2e: 3e (98: 2) 98 P-~3-w-4 6 mns-lf CdHsm 2f:3f (98:2) 90 ____________1____1~__-_~_~_c-~l-~-~~_~~~~~~-~-~-~~~~-~~~~-~~~~~~-~-~-~~--~~-~~~-~-~-~~~-~-~~~~~ 7
Cis-Ia
8
&-lb
9
cis-lc
10
&-Id
11
cis-le
12
cis-If
H
2a:3a
(1:99)
92
2b:3b
(0: 100)
88
2c:3c
(1:99)
92
2d:3d
(1:99)
93
P-=3-wJ4
2e:3e
(3:97)
95
c6Hga
2f:V
(3:97)
89
Bun csws
2181
octllcarboaylt0givcthelabilccoInllt~~
lmmEpoxide(&w?s-la)wasl.lcatdwithdimbalt
t of BF3.QEtz1 1 in CH2Cl2 at -78oC ptthchg
dcrivativcwbichwassu~tlyexposultoacatalytkaamtm theaelMhpt&uctsl2ia65%yicld.I3
‘Iberatiod~to~(cis:aMs)warfoaadtobe%:4~1).
No
5cxocyciizationpmduct3muldbe~Tbecamrpoadhrgcisepoxide(cis-~)~~~products (&:amrr=1:99)@nay7).
cxclusivelyin92%ylcldinal@gItlyaMssekuivcmarna
Furtkrucatnplesofb
ado~depmdder1v&tbcoIlrrwpoading-y-altnp~uada~alnditiotls
azpnstt&dinTabk.
TbcfolIowhgfeatumsdesetvc
cuttment.(i)Excluslvefhmatkmd6utdopnc&ctswas
obsuvalltgardlessofganncayofthclrtartiagacerytenicepoxidel. (ii)RingfomMiontookplaa?with ~~~~adcoafiguratioaatthepmpynylposirioansuhinginahighly~~fonnationdtronr-2 ethynyl-3-hydroxyauah~
systems from cis cpoxitk& whueas cis congencrs fam tranr cpoxides. (iii)
Imspectiveof~ekcbronicpapatiesofdretandnalMlbrcituwtonthttriplebondringc~plDaededinthe 6-aldomodccxclusivclyatld5-cxopoduces~nc~foundittmolttllaltaacequantitiw.
Itshauklbe
mentionedhatdrattwopossibleisomerizatioa~~cyclizatioa,i.c.epimrizationof2~33andce ttat&mnatiat ofa&altsattplcxccl fivz mcmbcral p&ucts (tcMtydt&ran dcrivtui~) to 2 wmdring (i) Pure 2b and and/or 3 (tethydropyran derivatives). wm complctiy ruled out by the following -lx 3b wue indqmhudy cxpsai to BF3a (0.1 cquiv.) in CH2Cl2 at -78% Rbactiaos quenched at the same tempcmturcl4Evcalcdthat lKHwziotlm&placcandaIbalt-almp~2baud3bwacrwpectinly~~ intact. (ii) Inhpmdcnt mnt oftctrahyhfkans 4b and Sbl5 with BF30Rt2 at -78“C ptovidcd only 4b alld5bEspcctivclyimactagain.
lEc.scisamerizptian~stmaglyiadicaattltat6-al&cyc~
p1r1ducts2and3a1ekktkaUycantrolkdintkrsecyclizathrwctians.
Reftrettus and Notes For nxxxtt reviewar. see (a) Rae, A.S.; Paknihr, SK.; Kirtane. J.G. Temahedron 1!&3,39,2323. (b) 1 Buivin, T.L.B. Tetrahcciron1987.43,3309.
2182
2
Far some xeccnt example& see (a) Fukuyama, T.; Wang, C.-I&
Kishi, Y. J. Am. Chem. Sec. 1979,
101,260. (h) Fukuyama, T.; Akasaka. K.; Kmncwslry, D.S.; Wang, C.-LJ.; S&mid, G.; Kid& Y. J. Am. Chm.
Sot. 1979,101.262.
(c) Schultz, W.J.; Ettex, MC; Purius, A.V.; Smith, S. J. Am. Cium.
Sac. 1980, ZUZ, 7981. (d) Dolle, RX.; Nicolaou. KC. J. Ant. C&m. SW 19e85,107,1691. Baztlett, P.A.; Ting, P-C!.J. Org. Ckm. 1!&6,51,22?0. 1988,29,2927.
(e)
A. Temhedroti Lm
(f’)Trast, EM.; Tenqlia,
(g) Maztfn, V.S.; Nuke, MT.; Ramirez, h&A.; Sol&, M. A. Tctmht?dro~ i&t. 1990.
32,763. (h) Kozikow&i, A.P.: Lee, J. .I. Org. Ckm. 1990,55,863. 3
(a) Nicoluou, K.C.; Rasad, C.V.C.; Somers. P.K.; Hwang, C.&J. (b) Nicolaou, KC;
Am. Chem. Sot. ~989,112.5330.
Frasad, C.V.C.; Somers, P.K; Hwang, C.-K. 3. Am. C/fern. SM. 1989, lil,
5335. 4 5
Sun&i, T.; Sato, 0.; Hirama, M. Tc@&&on
L&t. li990,3f,
4747.
For some I#xnt reviews, see (a) Mom& R.E. Marine NatwalProducts: Perspec&es;
Ntzzurul& Occruring Acid fonophorcs; Wmtley, J.W., E&, &lad D.J. Nar. Prod. Rep. 1986.3, 6 7
Dekker: New York, 1982. (c) Fau@mer,
The txmespmding cis epoxidcs have heen shown to disfavor dendo male of ring closmc3~b Tms$f alsorepinedpa&uIium+atalyxed &c&o cyckation of the hydmxy vinyl epoxide Unou8h %-ally1 statement
ofsbzockmicai outcome.
8
Baldwin. J.E. f. Chem. Sot., Chem. Commttn. 1976,734.
9
Janda, RD.; Shcvlin, C.G.; Lemer, R.A. Seieme, 19P3,259,490. During preparation of this manuscript, Nicholas reported examples of carbon-carbon bond formation with retention of stemockmistry
at the propynyl position of cobalt-complexed pqxqyl
tris(l,l,l,3,3,3-hexafluoroisopropyl)phosphite Ckm. 11
Antibiotics:
1.
palladium complexes without &Ink
10
Chemical und Bi&gicsl
Scheuer, P-J., E& Academic Ress: New Yock, 1978, ~012. (h) Polyerk
Sot. 1993,115,
~~~~~~~ ste~~lectivity
alcohols possessing
as a ligand. Caffyn, A.J.M.; Nicholas, K.M. J. Am.
6438
*c~~rnc~~~~~~~~c~~e~~ to those with BF3aEQ However, other Lewis scids (SnC&, TiCl4. EtAICi2, &?Alc%
were found to k infuiu
to BF3=OEtz
12
3-Hydroxytetmhydmpyrans 2 and3 were fully characterized by their convcffion into comsponding
13
6%aoetylcompounds without cobalt ccxnplexatiuo &rough successive CAN treatment and acetylatioo. Ring opening of coz(co)(i-conplexed l~~~xy-l~~~y~cl~~ with excess of Hfl, MeOH, or C13CCO2Hunderacidiccondition (HBF4Me20 ar H2saQ) hadbeen investi&%d in Sak, U; Nicholas,
14
K.M. J. Org. Chem. 1984.49.417. Even when c&lb was exposed to 1.0 equiv, of BF3aEt2
at -78°C no con%rsion of &-lb
to fmns-lb
could k oke~ed. However, isomer&a&m of c&-lb to tronr -lb (c& : tronr 8:26 : 74; 96% yield) ouxred upon treatment of theformer with 1.0 equiv. of BF3d3Et2 atrtfor 30 min,whams ram-lb
was
stable enough not to isomcsizc to c&lb under these conditions examined. 15
Cobaltemplexed tetrahydrofunms 4b and Sb watt &ived neattnent with Co2(CO)8: see the followingmanuscript.
16
For a mview, see Nichoias, KM. Ace. Chem. Res. 1987,20,207.
17
(a) Schreiber, S.L.; Sammakia, T.; Ckowe, WE 1. Am. C&m. Sot. 19&108,3128.
from the m-g
S.L.; Klimas.M.T.; Sammakia, T. J. Am. Chem. Sot. 1987,209, 5749. (Recebed &sJapan 23 Octok- 1993;accepted 18 January 19%)
tefrah~s
by
(b) Schmiber,