Reaktion #335318

ord-c162315141934898b8ef634f75735e1c

Reaktionsgleichung

Brc1cccc(Br)c1
1,3-dibromobenzene
OBO
boronic acid
Brc1cccc(Br)c1
1,3-dibromobenzene
CC(C)OB(OC(C)C)OC(C)C
triisopropyl borate
[Na+].[OH-]
sodium hydroxide
[Li][CH2]CCC
butyl lithium
OBO
Boronic acid
Ic1ccccc1
iodobenzene
O=C([O-])[O-].[Na+].[Na+]
sodium carbonate
Brc1cccc(-c2ccccc2)c1
3-bromo biphenyl

Lösungsmittel

Reaktionsbedingungen

Detaillierte Bedingungen
See reaction.notes.procedure_details.

Vorschrift

Starting with readily available starting materials, 1,3-dibromobenzene and the appropriately substituted iodobenzene, it is possible to prepare biphenyls having 3', 4' and 5' position substitution. Referring to Flow Sheet AE 1,3-dibromobenzene AE1 is converted to boronic acid AE2 by first reacting with butyl lithium in anhydrous THF or ether at about -78° C. followed by addition of triisopropyl borate. The resultant intermediate is worked up with sodium hydroxide and acidified. Boronic acid AE2 is subsequently reacted with the appropriate iodobenzene AE3 in toluene and aqueous sodium carbonate with tetrakistriphenylphosphinepalladium as a catalyst to produce the 3-bromo biphenyl B1. This reaction to B1 is well known in art with reference made herein to N. Miyaura, T. Yanagi and A. Suzuki, Syn. Comm., 11, 513 (1981). ##STR19##

Quelle

DOI: 10.6084/m9.figshare.5104873.v1Patent: US05208329uspto-grants-1993_05