[skp524]

What product(s) will be formed when Br-(CH2)4COH is mixed with Na+-CCH?
Will the acetylenide be added to carbonyl carbon ,displace Br simply or react in both manner? (1mole equiv.)

[discodermolide]

What product(s) will be formed when Br-(CH2)4COH is mixed with Na+-CCH?
Will the acetylenide be added to carbonyl carbon ,displace Br simply or react in both manner? (1mole equiv.)

How about the tetrahydrofuran substituted in the 2 position with an acetylene? (Attack at the aldehyde carbonyl followed by ring closure of the O- at the Br substituted carbon atom.)

[azmanam]

Are you describing 5-bromopentan-1-ol, or 5-bromopentanal - because you'll get different answers.

It sounds to me like you'll get tetrahydropyran as the product, because the structure you draw is the alcohol.  But you say in words the carbonyl carbon.  In that case, I'd expect the alkyne to both displace Br and nucleophilically add to the aldehdye.  That would give you something like 1,8-nonadiyn-3-ol.

[skp524]

Are you describing 5-bromopentan-1-ol, or 5-bromopentanal - because you'll get different answers.

It sounds to me like you'll get tetrahydropyran as the product, because the structure you draw is the alcohol.  But you say in words the carbonyl carbon.  In that case, I'd expect the alkyne to both displace Br and nucleophilically add to the aldehdye.  That would give you something like 1,8-nonadiyn-3-ol.

Um.. if aldehyde (HC=O) is replaced by amide (H2NC=O) , will it similarly yield di-functional compound?

[azmanam]

to a first approximation, yes.  if you want the aldehyde to stay, and the alkyne to displace the bromide, then keep the aldehyde, protect it as a cyclic acetal, displace the bromide with the acetylide, then deprotect to reveal the aldehyde.