Brown, Herbert C. published the artcileChiral synthesis via organoboranes. 7. Diastereoselective and enantioselective synthesis of erythro- and threo-β-methylhomoallyl alcohols via enantiomeric (Z)- and (E)-crotylboranes, Name: (+)-B-Methoxydiisopinocampheylborane, the publication is Journal of the American Chemical Society (1986), 108(19), 5919-23, database is CAplus and MEDLINE.
Isomerically pure (Z)- and (E)-crotylpotassiums were prepared by metalation of (Z)- and (E)-2-butene using a modified Schlosser procedure. The enantiomerically pure (Z)-crotyldiisopinocampheylboranes I and II were prepared by employing methoxydiisopinocampheylboranes, prepared from either (+)- or (-)-α-pinene, resp., and (Z)-crotylpotassium I and II retain their stereochem. identity under the reaction conditions and were condensed with RCHO (R = Me, Et, H2C:CH, Ph) regioselectively and stereoselectively to yield the corresponding erythro-β-methylhomoallyl alcs. e.g., III, in ≥99% diastereoselectivities and ≥95% enantioselectivities. Similarly, the enantiomeric (E)-crotyldiisopinocampheylboranes were prepared and add to RCHO to yield the corresponding threo-β-methylhomoallyl alcs. with similar selectivities. Further, (Z)- and (E)-crotyldiisocaranylboranes IV were prepared and condensed with EtCHO to furnish the erythro– and threo-β-methylhomoallyl alcs., resp., in ≥99% diastereoselectivities and improved enantioselectivities (97%).
Journal of the American Chemical Society published new progress about 99438-28-5. 99438-28-5 belongs to ethers-buliding-blocks, auxiliary class Chiral,Aliphatic cyclic hydrocarbon, name is (+)-B-Methoxydiisopinocampheylborane, and the molecular formula is C21H37BO, Name: (+)-B-Methoxydiisopinocampheylborane.
Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem