203189-64-4Relevant academic research and scientific papers
Asymmetric synthesis of axially chiral biaryls via desymmetrization of 2,2′,6,6′-tetrahydroxybiphenyl using 1,4-Di-O-benzyl-L-threitol as a chiral template
Mai, Tran,Tuyet, Thi,Harada, Toshiro,Hashimoto, Kazuyuki,Hatsuda, Masanori,Oku, Akira
, p. 1335 - 1343 (2007/10/03)
Sequential etherification of 2,2′,6,6′-tetrahydroxybiphenyl (1) with 1,4-di-O-benzyl-L-threitol under Mitsunobu conditions gives desymmetrized biphenyldiol 9 of S-axial chirality exclusively. Cyclization of 9 with l, u-dibromoalkanes followed by removal of the chiral auxiliary yields (S)-2,2′-biphenyldiols 14 with alkylenedioxy bridges at the 6 and 6′ positions. (S)-6,6′-Dialkyl- and -diphenyldiols 20 are obtained in an efficient manner via Pd(0)-catalyzed cross-coupling of bis(triflate) derivative 17 with organozinc reagents. Bis(triflate) 17 also serves as an intermediate for asymmetric synthesis of axially chiral biphenyldicarboxylic acid 23, terphenylcarboxylic acid 28, lactone 26, and lactam 30.
Asymmetric desymmetrization of 2,2′,6,6′-tetrahydroxybiphenyl by using 1,4-Di-O-benzyl-D-threitol as a chiral template
Harada, Toshiro,Tuyet, Tran Mai Thi,Hashimoto, Kazuyuki,Hatsuda, Masanori,Oku, Akira
, p. 1426 - 1428 (2007/10/03)
A general method for the preparation of axially chiral (S)-6,6′-disubstituted 2,2′-biphenyldiols is developed by using a highly enantioselective desymmetrization of 2,2′,6,6′-tetrahydroxybiphenyl.
