[dtaru]

Which is the best sequence of steps for carrying out the synthesis shown?


1. (1) SOCl2; (2) Mg, diethyl ether; (3) (CH3)2CHBr

2. (1) (CH3)2CHMgBr in diethyl ether followed by H3O+; (2) Na2Cr2O7, H2O, H2SO4

3. (1) LiAlH4 in diethyl ether followed by H3O+; (2) PCC, CH2Cl2; (3) (CH3)2CHMgBr in diethyl ether followed by H3O+ ; (4) PCC, CH2Cl2

4. (1) NaBH4 in diethyl ether followed by H3O+; (2) PCC, CH2Cl2; (3) (CH3)2CHMgBr in diethyl ether followed by H3O+ ; (4) Na2Cr2O7, H2O, H2SO4

[dtaru]

I forgot to add I think that the answer is number 1.  Not to sure about it though.  Any help would be greatly appreciated.

[discodermolide]

No, I don't think the answer is number 1. Grignards will not form from acid chlorides as they react with themselves.

[dtaru]

So then what do you think it is?  I'm a bit confused now :/

[discodermolide]

I suggest it is number 3.