Intramolecular Reformatsky reaction product

Asymmetric intramolecular Reformatsky reactions/ The bromoacetates (1) of (3-hydroxy ketones undergo a Reformatsky-type reaction when treated with Sml2 to give (3-hydroxy-8-valerolactones (2). These products are useful in their own... 

Following a similar strategy, the synthesis of tetracyclic models of aziridinomitosenes, bioactive degradation products of mitomycins, was based on the Reformatsky reaction of thiolactam 100, as shown in equation 59. The synthetic plan and reagent design were directed to the use of an intramolecular Heck reaction of 101 to complete the target skeleton146. 

Intramolecular Reformatsky-type reactions a-methylene-t-lactones. Reaction of the (Z)-bromoaldehyde (1) in a dilute solution of THF with zinc dust at 65° or with zinc-copper couple at 25 leads to the c/i -fused a-methylene-y-lactone (2) in 60-62% yields. The reaction involves an intramolecular Reformatsky-type reaction followed by spontaneous lactonization. The same product (2) is also obtained from the (E)-isomer of (1) in 46% yield together with the transfused isomer of (2). The reaction of (1) with bis(l,5-cyclooctadicnc)nickel (4, 33-35 5, 34-35) also yields (2) in 527 yield. It is obtained in comparable yield... 

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