[palesuvi]

Hi,
Does anybody have real experiense in 2,2′-Dibromo-1,1′-binaphthyl syntesis?
Published method of reaction 
Binol with triphenylphosphine dibromide leads to extremely low yeld (less than 20%) and difficulties in reaction mixture separation.

[Babcock_Hall]

What is the reference to the published synthesis, and what was the yield?  Do you think that poor separation is related to your yield's being low?

[rolnor]

I think its a sterically very crowded molecule and only one step-synthesis so even 20% is not so bad. Do you want to make large ammounts?

[kriggy]

You probably want to protect the oxygens and then do lithium-halogen exchange.

Quick search on reaxys revealed multiple papers reporting this sequence with over 90% yield for each step. Probably better way to go if you need high amounts of material

https://pubs.acs.org/doi/10.1021/ol0490882

https://pubs.acs.org/doi/10.1021/jo051176s

There is a patent as well covering the topic
https://worldwide.espacenet.com/publicationDetails/originalDocument?CC=EP&NR=1623971A1&KC=A1&FT=D&ND=&date=20060208&DB=&locale=en_EP
see examples at page 15 and 16

[rolnor]

I diont get it, there is no hydroxyls in 2,2-dibromobinaphtyl?

[kriggy]

Oh wait.. nvm I missread the title, thought its bromo-BINOL