Abstract
Arylation and alkenylation of aromatic aldehydes with silanediols is shown to proceed by use of a catalytic amount of rhodium complex. Treatment of ethyl(4-methoxyphenyl)silanediol with benzaldehyde in the presence of 3 mol% of [Rh(OH)(cod)]2 affords 4-methoxyphenyl(phenyl)methanol in 59% yield after stirring at 70 °C for 24 hours. On the other hand, diarylketone was also obtained at elevated temperature via β-hydride elimination from intermediary rhodium alkoxide.
Key words
silanediol - rhodium complex - arylation - alkenylation - aldehyde
References
1a Effenberger F.
Spiegler W.
Chem. Ber.
1985,
118:
3872
1b Effenberger F.
Spiegler W.
Chem. Ber.
1985,
118:
3900
1c Mills RJ.
Taylor NJ.
Snieckus V.
J. Org. Chem.
1989,
54:
4372
2 Oi S.
Moro M.
Inoue Y.
Organometallics
2001,
20:
1036
3a Sakai M.
Ueda M.
Miyaura N.
Angew. Chem. Int. Ed.
1998,
37:
3279
3b Ueda M.
Miyaura N.
J. Org. Chem.
2000,
65:
4450
3c Ueda M.
Miyaura N.
J. Organomet. Chem.
2000,
595:
31
3d Oi S.
Moro M.
Inoue Y.
Chem. Commun.
1997,
1621
3e Oi S.
Moro M.
Fukuhara H.
Kawanishi T.
Inoue Y.
Tetrahedron Lett.
1999,
40:
9259
3f Li C.-J.
Meng Y.
J. Am. Chem. Soc.
2000,
122:
9538
3g Hayashi T.
Ishigedani M.
J. Am. Chem. Soc.
2000,
122:
976
3h Hayashi T.
Ishigedani M.
Tetrahedron
2001,
57:
2589
4a Hirabayashi K.
Nishihara Y.
Mori A.
Hiyama T.
Tetrahedron Lett.
1998,
39:
7893
4b Hirabayashi K.
Ando J.
Kawashima J.
Nishihara Y.
Mori A.
Hiyama T.
Bull. Chem. Soc. Jpn.
2000,
73:
1409
4c Hirabayashi K.
Kawashima J.
Nishihara Y.
Mori A.
Hiyama T.
Org. Lett.
1999,
1:
299
4d Hirabayashi K.
Mori A.
Kawashima J.
Suguro M.
Nishihara Y.
Hiyama T.
J. Org. Chem.
2000,
65:
5342
4e Hirabayashi K.
Kondo T.
Toriyama F.
Nishihara Y.
Mori A.
Bull. Chem. Soc. Jpn.
2000,
73:
749
(f) Hirabayashi K.
Mori A.
J. Synth. Org. Chem. Jpn.
2000,
58:
926
5 Mori A.
Danda Y.
Fujii T.
Hirabayashi K.
Osakada K.
J. Am. Chem. Soc.
2001,
123:
10774
6 Huang T.
Meng Y.
Venkatraman S.
Wang D.
Li C.-J.
J. Am. Chem. Soc.
2001,
123:
7451
7a Ishiyama T.
Hartwig JF.
J. Am. Chem. Soc.
2000,
122:
12043
7b Hirao T.
Misu D.
Agawa T.
J. Am. Chem. Soc.
1985,
107:
7179
8
Experimental : To a mixture of ethyl(4-methoxyphenyl)silanediol(1 ) (119 mg, 0.6 mmol) and [Rh(OH)(cod)]2 (4.1 mg, 0.009 mmol) in 2 mL of 1,4-dioxane under argon atomosphere was added 4-methoxybenzaldehyde (0.037 mL, 0.3 mmol). Stirring was continued at 100 °C for 24 h and the resulting mixture was concentrated and subjected to column chromatography on silica gel (hexane-ethyl acetate, 20:1-3:1) to afford 35 mg of bis(4-methoxyphenyl)methanol (47%) and 17 mg of 4,4"-dimethoxybenzophenone (23%). (Rf = 0.22 and 0.35, respectively with Hexane-EtOAc, 3:1).
