close

Вход

Забыли?

вход по аккаунту

?

Optically Active Lactones from a BaeyerЦVilliger-Type Metal-Catalyzed Oxidation with Molecular Oxygen.

код для вставкиСкачать
COMMUNICATIONS
[XI M. Weidenbruch. A. Schafer. H.
C/IOli
KiIi:iii.
S. Pohl. \V. Saak. H. Marsinann.
Bw. 19Y2. 175. 563.
[Y] A . Schafcr. M . Weidenbruch. W. S u k . S. Pohl. H. Marsmaun. Aiigeii. C'/iwii
1991. 103. 873. 978: ,4ilgPIr'. C'/i?ni. /n/. E d €n,q/. 1991. 30. 834. 962.
[ l o ] F. J. Brady. C J. C'irdiii, D. J. Cardin. M. A . Convcry. M . M. Devereux. G A
Lau,less. J O r x o i i o i i i r / . Ciicvii 1991. 42/. 199.
[I I ] M . Weidenhruch. K . Schdl'trs. S Pohl. W Saak. K . Peters. H. G . von Schnering. J. O r g i i i i o i i i i ~ t C / i i w i . IY88. 346, 171.
(121 J. Prey. D. A Nugiel. Z. Rappoport. J Ovg. C/iwi. 1991. 56. 466.
[13] M . J. S Glane. D H. Harris, M. F. Lappert, P. P. Power. P. Riviire. M . Riviere-B,tudct. J C ' l i t w i . SO(..
DNIIOIZPuiis. IY77, 1004.
(141 M. Weidenhruch. K.Krmier. J Or,qoiioiiicr. Chcw 1985. 3YI. 159.
[I51 X-ray crystal structure analysis o f 9 : C,,,H,,Sn. h ,= 609.57. orthorhoinhie.
space group P k n . ii = 1767.3(4). h = 19 ?(4). I ' = 205Y.6(5) pm. 1' =
6971(3)x 1OhpmJ. L = X. pillLd
=1.161 g c
'. Mo,, radiation, graphite
monochroinator. 20,,,, = 55 . Wyckoff-scan. X730 independent reflectionr.
5738 observed independenr reflections ( F 3 n ( F ) ) .<:parameter r;itio = 17.2.
Solution by direct methods and refineineiit with t h e Siemens-SHELXTL-Plus
progmm sqstem. R = 0.050. R, = 0.046. Further derailsofthccrystal structure
investlaation may he obtained from the Fachinforinatioiis~entrumKarlsruhc.
D-76344 Eggenstein-Lropoldsli~ifen ( F R G ) . upon quoting the depository
numher CSD-400727.
[I61 The existence of(impure) 9 was presumed on the bask of ils Mdssbaucr spectrum: M. P. Biguood. P. J. Corvan. 1. J. Zuckernian. J. A m . C/imi, So<.. 1981.
103. 7643.
[17] H GI-Gt~macher.H. Pritzkow, E T. Edelmann. Oi~[ii7"1~i[,"'//ic.r,
1991. ill. 2 3
A second crystalline form of 10 with a weak tin- tin interaction is described: U
Lay. H . Pritzkou. H. Grutzmacher. J. C/icw. Soc. C'heni. Corwiiuri. 1992. 260.
1181 Y . Tokitoh. M. Saito. R. Okazaki. J A m . C/iciii. Soc. 1993. ll.5. 2065.
1191 M. Kira. R. Yauchihara. R. Hirano. C Kahuto. H. Sakurai. J. A i i i C/iwi. So(
1991. 113. 77x5.
[2l)] M. Veith, 0 . Recktcnwald. Top Curr. C h i . 1982. 104. 1.
[21] B. Wmcknieycr, J ,Mri,qii. Rer. 1985. 61. 536.
I n the presence of an aldehyde and a metal catalyst, cyclic
ketones are oxidized to lactones with molecular oxygen.'" '1 We
chose 2-phenylcyclohexanone ( I a) as the model compound for
our investigations into the asymmetric oxidation reaction, because 1 a is converted into lactone 2 a in high yields and with
good regioselectivities in the reaction catalyzed by achiral nickel
and copper complexes.[sl The enantiomeric excesses (cc) ob-
rac-1
a: n = 1, R = Ph
b: n = 1, R = 4-CI-Ph
c: n = 1. R = 4-MeO-Ph
d: n = O , R = P h
cat.* = Ni or Cu complex with chiral ligands
tained for lactone 2 a and ketone 1 a can be determined reliably
and unambiguously by HPLC on a chiral column. With the
optically active nickel(r1) complex 3a. rac-1 a was converted to
r.uc-2a, regardless of the reaction conditions employed; with the
corresponding copper complex. 2a was obtained with enantioselectivities of up to 69 o/o re.
3a: M = Ni, R = Alkyl, X = H
b: M = C U ,R = ~ B uX, = NO2
C: M = Cu, R = tBu, X = H
d: M = Cu, R =iPr, X = NO2
e: M = Cu. R = iPr, X = H
C a r s t e n Bolm,* G u n t h e r Schlingloff, and
Konrad Weickhardt
[*I
Prof. Dr. C. Bolm ['I. DipLChem. G. Schlingloff['], Dr. K . Weickhardt
lnstitut fur Organische Chemic der Uniwrsitlt
St. Johanns-Ring 19, CH-41)SO Basel (Swirzerland)
[ ' 1 New address. Fachbereich Chemie dcr Universitiit
Hans-Meerweiii-Straase. D-35032 Marhurg ( F R G )
Telefax: Int. code + (6421)28-8917
[**I This research w n s supported by thc SchNeirerischer Nationalfonds and the
Deutsche For~chun_psgemeiiisch~i~t
(project: oxygen transfer peroxide chemistry) We thank Profecsora Pfaltz and Schiess. Uni\,ersitiit Basel. for samples.
(SJ-1
e: n = 2 , R = P h
Optically Active Lactones from a
Baeyer -Villiger-Type Metal-Catalyzed
Oxidation with Molecular Oxygen**
Catalyzed asymmetric oxidations are of paramount importance for the synthesis ofchiral building blocks. Enantioselectivities of over 90 YOhave been achieved in the dihydroxylation of
olefins"] and in the epoxidation of ally1 alcohols'2J and nonfunctionalized cis a l k e n e ~ . ' ~In
] general. highly oxidized
reagents. such as peracids or other peroxy compounds, are employed as the source of oxygen. M u k n i j w m et al. reported that
molecular oxygen could also be used as a simple oxidizing agent
in the asymmetric oxidation of oletins provided that an oxygen
acceptor. such as an aldehyde. were present in stoichiometric
quantities.141As part of our investigations into the activation
and transfer of oxygen.[51we have now developed an enantioselective, metal-catalyzed variant of the Baeyer-Villiger oxidation. a reaction which had previously only been achieved with
the help of enzymes."]
(RJ-2
In order to achieve good reactivity and high asymmetric induction, several reaction parameters had to be optimized. The
best results were obtained with p-nitro-substituted copper complex 3b in water-saturated benzene and with pivalaldehyde as
the oxygen acceptor ( = coreducing agent) (Table 1). Use of
1 mol O/O of (S,S)-3b as catalyst at room temperature and under
an oxygen atmosphere resulted in formation of lactone (R)-2a
in 41 % yield and 65 O/O cc after 16 hours; at 6 -C. an increase in
Table I . Enantioselccti\,e Baeyer Villiger oxidation of cyclic ketones with (S.S)3 h.
Entry
Aldehyde
Ketone
rBuCHO
rBuCHO
iii-CI-PhCHO
p-MeO-PhCHO
{BuCHO
C,H, , C H O
fBuCH0
rBuCH0
rBuCHO
la
la
Ia
Lactone
Yield ['%I
ec'
41
41
32
65
69
49
1a
la
la
-
lh
43
53
21
lc
Id
65
61
["%I
[a]
59
61
ca 60 [el
65
47
[a] Determined by HPLC o n a chiral phase. [b] 6 d at 6 C. [c] Reaction time 5 d. [dl
The absolute configuration was not determined. [el N o base-line separation.
COMMUNICATIONS
enantioselectivity was observed (69 % re). Since the unreacted
ketone was enriched in enantiomer (S)-1a.[81the lactone formation formally corresponds to a kinetic resolution. The "overoxidation" product, 6-0x0-6-phenylhexanoic acid (4),was isolated as a
byproduct. In the absence of an
OH
P
h
k
aldehyde, copper-catalyzed oxida0
tions with molecular oxygen ''1 I so re4
sult in formation of 4.19- Lactone
2 a was found to be stable under the
reaction conditions and was not oxidized to 4.The reaction was
suppressed when 5 mol YOof catalyst, 2.6-di-tert-butylcresol as a
radical trap. or an excess of the free ligand 5 were used.['21
Racemic lactone was obtained in the presence of molecular
sieves (4
or solid NaHCO,. Only small or negligible quantities of lactone were formed in other solvents, such as. ethyl
acetate. acetone, rcw-butyl methyl ether, acetonitrile, cyclohexane. toluene. or 1.2-dichloroethane. which was the solvent used
in the Ni-catalyzed reaction.[51Aromatic aldehydes did not give
satisfactory results as coreducing agents in the Cu-catalyzed
reaction; even with longer reaction times, poorer yields and
eiiantioselectivities were obtained (Table 1, entries 3 and 4).
The 1 : 1 complexes obtained from copper(r1) trifluoromethanesulfonate and the C,-symmetric bisoxazolines 6 8113. 14.11 also catalyzed the formation of optically active 2 a ; the
yields and enantioselectivities were however poor: with 6,39%0
yield ( I 2 %O w): with 7, 39 % yield (25 % r e ) ; and with 8, 25 YO
yield (1 2 '%, c e ) .
A)
We are currently working on elucidating the course of reaction and on other oxidation reactions with the new catalysts."']
E.vperitnental Procedure
The ketone ( 1 inmol) and lhe catalyst (10 pmol) were dissohcd i n water-saturated
benzene (2.5 niL) and treated with the aldehyde (0.5 mmol) and wiikr ( I00 ~ I L The
)
inixture wit\ stirred under ;in oxygen atinosphere for 16-20 A. diluted with diethyl
ether (150 mL). and washed with saturiited aqueous NaHCO, wlution ( 5 0 i n L ) .
The organic phase was dried over Na,SO,. After removal o f the wlbent, thc crude
hromatographed on silica gel The eniintioineric exces~esfor I and 2
were determined by HPLC. when necessary. ;dter bulb-to-bulb distillalion under
high bacuum [Chiracel ODH (Daicel): flow rate 0.5 i n L m i n - I : for 2 a : UV detector
(254 nm). 2-propanol.'hexane 1.3. retention timey: (S)-2a: 12 4 min, ( R ) - Z a .
16.0 min: for l a : UV detector (220 n m ) . 2-propanol'hexane 1 ' 9 . rctention ~ i m c i :
( S ) - l a : 14.5min. ( R ) - l a :15.7minl.
Received: April 2X. 19Y4 [ZhX76IE)
Gcrmon version. Arigc~it,C'liwn 1994. /(Mi. I944
a ) Ciiralvic i l . 5 ~ 1 i r n t ~ i r i.cS j - n i t i r ~ \ i . ~(Ed.: I . Ojimii). VC'H. Wuinhcim. 1993:
b) R. A. Johnson. K. B. Sharpless in ref. [I a], pp. 227 -272.
R. A . Johnson. K. B. Sharpless i n ref. [I a ] pp.
~ 101 - 15X.
E. N . Jacobsen in ref. [I a], pp. 159-202.
a ) T. Y'iniad;i. K. Imagawa. T. N e p t n . T Mukaiyania. C / i w . L c / r . 1992.
2231 -2234; b) 7 Mukaiyxmi. T. Yamada. T. Nagata. K . Imagiwa. ;hid 1993.
327-330.
C. Bolni. G. Schlingloff. K. Weickhardt. R,r,vrlidrori Lrti. 1993. 34. 3405
340x
a) F. Petit, R. Furstoss. 7i.rrahrrlrciri .4.sininwrri 1993, 4. 1341 1352: b) V.
Alphand, R. Furstoss. J Org. Cheni. 1992. 57. 1306--1309: c ) M. _I. Taschner.
L. Peddada. J, C/zmi. Soc. C'hrni. C O N I I ~ I1992.
I I I I 13x4
.
- 13x5: d ) G. (irogan.
S M. Roberts. A. J. Willetts. ihid. 1993. 699- 701; e ) 0. Abril. (.. C. Ryerson.
C. Walsh. G. M Whitesides. Bioorg. Chriii. 1989. 17. 41 52: f ) For r
~
~
R
R
5a: R = r B u , R = i P r
b: R = H, R = rBu
R = NOz, R = rBu
C:
The steric and electronic properties of the ligand influence the
activity and enantioselectivity of the catalyst. Higher yields were
obtained with thep-nitro-substituted complexes 3 b and 3d than
with the corresponding unsubstituted compounds 3 c and 3 e ;
the enantiomeric excesses obtained were not always higher: with
3b, 41 70yield (65% r e ) ; with 3c, 29% yield (57% e r ) ; with 3d,
5 7 % yield (32% r e ) ; and with 3e, 34% yield (36% ee).
Without the tert-butyl substituent on the arene (5 b and
5c),[14] the ligand formed copper complexes which were only
weakly active (yield < 1 0 % ) . In the substrates, electronic effects
play a secondary role. The p-chlorophenyl- and p-methoxyphenyl-substituted ketones 1 b and 1 c were transformed into
lactones 2 b and 2 c with very similar enantioselectivities
(Table 1. entries 7 and 8). The dependency of reactivity on ring
size corresponds to that observed for per acid^:^'^.'^] l a was
oxidized fastest, 1 d slower (Table 1, entry 9), and 1 e not at all.
The alkyl-substituted cyclic ketone 2-cyclohexylcyclohexanone
and the positional isomer 4-phenylcyclohexanone did not react.
see: C. T. Wdsh. Y.-C. J. Chcn. A r i , q ~ w .C h i t . 1988. / / X I . 343 352, Angvii.
Clicni. l i i r E d G I X /1988,
.
27. 333-343: and references thcrein.
a ) T. Yamada. K. Takahashi. K. Kato. T Txkai. S. Inoki. T. M u k a i y a m , ~ .
C ' h ~ l 7 Lerr.
.
1991. 641 - 644; b) S.-I. Murailashi. Y. Oda. T. Naota. 7 i ~ r i d i c ~ ~ h . o i i
Lerr. 1992. 33. 7557- 7560; c) M. H;iinanioto. K . Nakay;iin;i, 1: Ni~liiy~iina.
Y.
Ishii. J 01.x.C/ieii?.1993. 58. 6421 -6425; {I)K . Kaneda. S. lieno. T 1m:inak;i.
E. Shimotsuina. Y Hishiyama. Y Ishii. h d 1994, 5Y. 2915 2917
The enantiomeric excess obtained for thc ketonc after purilic~tiun by chromatography on silica gel (46 7596 yield) ranged betuecn 1 0 a n d 30'%. depending on the reaction conditions. For the absolute configtirution of I a. see: G
Bcrti. B. Macchia. F. Macchia, L. Monti, J. Chrrii. So<.C' 1971. 3371 ?375. To
establish the configuraLion ol'2a. (S)-Ia was oxidired b b i t h iii-chloroperbenLOIC acid.
In the Cu"-catalyzed oxygenation of carbonyl compounds. coppei- enolate.;
may also bc involved. a) S:J. lin. P. K Arora. 1.. M Sayre. .I O i y C/i(wi IYYU.
Xi. 301 1-3018: b) L M. Sayre. S.-l. Jin. ihid. 1984. 49. 3498 3503.
Analogous products ucre obtained with other metal catalysts. a ) S. 110, M
Matsumoto. J Orx. C ~ / w r i i .1983. 48, 1133 1135, b) T. Hir;u,. M Mori. Y.
Ohsbiro, Bid/. Chcm. So<,.Jprr 1989. 62. 2399-2400: c ) A Atlanisani. .I.-M.
BrCgCdult. M . Ziyad. ./. Org. Chcrn. 1993. 58. 5663 5665.
In the absence of aldehyde. the starting material isolated from thc rraction o f
I a with 3 e in toluene (73% vield) was found to be enriched in ( R ) - l a (8':;) C P )
[12] Carried out with 3 e in benzene: inhibition with the free Iignnd S a .
[I31 A. PfaltZ. Ace. C'hW77. RW. 1993. 26. 339-345.
1141 ii)C. Bolm, K . Weickhardt. M. Zelinder. T. Riinff. ( ' i i c n i . BIT 1991. I 4 .
1173-1180; b) C . Bolm, K . Weickhardt. M. Zehnder. D. Glasinacher. Ilc,li,.
Chini. i l ~ r r 1991,
r
74, 717-726: c ) C. Bolm. Iwgrvl-. C/ierii. 1991. / 0 3 . 556 5 5 8 .
.4ngeir. C%cni. I r i r . Ed. Eng1. 1991. 30. 542-543: d ) H. Yang. M . A. Khan.
K. M Nicholas. Org~rriu117~~rrr//ic.\
1993. 12. 34x5- 3494
[I51 a ) S. L. Friess. J Aiii. Ciirwi. Soc. 1949. 71. 2571 2575. b) (i. R . K r o w i n
Coni/,relioi.\i,.e or gun;(^ S~~17i17~3;.5,
kbl. 7 (Eds.: B. M. Trost. 1. Fleming). Pergamon. Oxford. 1991, pp. 671 -688.
[16] After 1 5 h in benzenehater under ai-gon and in the presence 0 1 I inol C:, (.T.S)3b, roc~Iaas oxidized with perncetic acid (40"/;, in acetic acid) to the I:ictonc
(R)-Za with 21 oh cc (46% yield). The ketone ( S ) - l a h a s isol;r~cdwith 21 '% w
( 3 6 % yield).
[I71 Cu"cat;ilyzes theeponidation of olefins with RCHO and 02:S.-I. Murnhashi.
Y. Oda. T. Naota. N. Komiya. J Clirni. Sor.. Chon. C~~~iii/ii~iii.
1993. I?9 140
Документ
Категория
Без категории
Просмотров
0
Размер файла
251 Кб
Теги
oxidation, optically, molecular, metali, lactones, activ, typed, baeyerцvilliger, oxygen, catalyzed
1/--страниц
Пожаловаться на содержимое документа