Highly Enantioselective Dynamic Kinetic Resolution of 1,2−Diarylethanols by a Lipase−Ruthenium Couple
作者:Mahn-Joo Kim、Yoon Kyung Choi、Sol Kim、Daeho Kim、Kiwon Han、Soo-Byung Ko、Jaiwook Park
DOI:10.1021/ol800163z
日期:2008.3.1
A practical procedure has been developed for the dynamickineticresolution of 1,2-diarylethanols. This procedure employs a highly enantioselective lipase from Pseudomonas stutzeri (trade name, lipase TL) as the resolutioncatalyst and a rutheniumcomplex as the racemizationcatalyst. Sixteen 1,2-diarylethanols have been efficiently resolved to provide their acetyl derivatives with good yields (95-97%)
Continuous Flow Preparation of (Hetero)benzylic Lithiums via Iodine–Lithium Exchange Reaction under Barbier Conditions
作者:Niels Weidmann、Johannes H. Harenberg、Paul Knochel
DOI:10.1021/acs.orglett.0c01991
日期:2020.8.7
benzylic lithiums via an iodine–lithium exchange reaction on benzylic iodides performed in continuous flow using tBuLi as the exchange reagent. The resulting benzylic lithium species are trapped in situ by carbonyl electrophiles under Barbier conditions, resulting in benzylic secondary and tertiary alcohols. This flow procedure further allows the generation of highly reactive heterobenzylic lithium compounds
An operationally simple, inexpensive and efficient procedure for benzylation of aldehydes in wet medium has been developed that was mediated with low valent copper, prepared in situ through spontaneous reduction of CuCl2-2H(2)O with magnesium in situ. Notably, copper mediated benzylation of 3h took place with good syn selectivity that was opposite to that for the corresponding Grignard addition. Finally, homobenzyl alcohol 5a was elegantly transformed into a known protease inhibitor synthon I.