GC_MS (Hive Bee)
10-07-02 01:07
No 365186
      phenol formylation via dithianes?  Bookmark   

The following is hypothetical - a dream - and is the result of a post SWiM made in the Tryptamine section - Post 360757 (Rhodium: "New tryptamine synthesis?", Tryptamine Chemistry)
SWiM has to apologize for the theoretical aspect of this post. Maybe SWiM should try it out in practice first before posting what he thinks. Imaginable, but SWiM is ill for a rather long time now, and he still won't be recovered (read as: able to work in his lab) this month. So he shoots this crazy idea, and you start (1) flaming me for this bullshit, or (2) start praising me for my spectacular find wink. Other interested bees might help develop the method or explain why it won't work.
OK, here it goes... The global idea is to perform a formylation of a phenol, more particularly 4-methoxyphenol.

(1) 4-methoxyphenol is activated in the meta position (relative to the hydroxyl group).

      H   H
 (d-) C---C
     /     \
HO--C       C--OMe
     \     /
 (d-) H   H
(2) reaction of 2-chloro-1,2-dithiane with 4-methoxyphenol

                            H   H                          H   H
  H2C---S   Cl              C---C                          C---C
   /     \ /               /     \                        /     \
H2C       C      +    HO--C       C--OMe    ---->    HO--C       C--OMe   +   HCl
   \     / \               \     /                        \     /
  H2C---S   H               C---C                H2C---S   C---C
                            H   H                 /     \ /    H
                                               H2C       C
                                                  \     / \
                                                 H2C---S   H
(3) reaction of 2-(1,3-dithiane)-4-methoxyphenol with Hg(II)

            H   H                                      H   H
            C---C                                      C---C
           /     \                                    /     \
      HO--C       C--OMe   +   HgCl2    ---->    HO--C       C--OMe
           \     /                                    \     /
  H2C---S   C---C                                      C---C
   /     \ /    H                                     /    H
H2C       C                                      O===C
   \     / \                                          \
  H2C---S   H                                          H

This "theorem" is based on the post mentioned in the beginning, and on Synthesis of New 2-(1,3-Dithianyl)phenols and Hexakis-[p-(1,3-dithian-2-yl)phenoxy]cyclotriphosphazene , Molecules (1997) pp 7-10. The article can be downloaded for free: http://www.mdpi.org/molecules/papers/jan97p3.pdf
This article demonstrates that substituted phenoles can interact with dithianes. The yields aren't superb, but the reaction seems feasible; a shame that the yields for MeO as para substituent aren't mentioned... The second part is the conversion of the dithiane part to -CHO. This can be achieved by hydrolization using Hg(II) - for instance HgCl2. This reaction is shown on http://www.tciamerica.com/news/newslib/94sum_a.htm
So, in short: reaction of a phenol with dithiane yields a dithiane phenol, which after hydrolization with Hg(II) gives a hydroxybenzaldehyde. If you wouldn't know by now, the target compound is 2,5-dimethoxybenzaldehyde wink.
Time to spit out your thoughts...

[EDIT] - Forgot to post about the synthesis of 2-chloro-1,3-dithiane... The synthesis of 1,3-dithiane can be found on Organic Synthesis: http://www.orgsyn.org/orgsyn/prep.asp?prep=cv6p0556 - the Molecules article SWiM mentioned uses succinylchloride to add Cl to 1,3-dithiane...

[EDIT 2] - If this thing would ever turn out to work, don't forget to send your gfs to pHarmacist... It was his post in the above mentioned thread and two pints of beer that made me dream about this synthesis.

WOMAN.ZIP: Great Shareware, but be careful of viruses...
(Hive Bee)
10-07-02 17:33
No 365507
      !  Bookmark   

Ok.. GC_MS send me your gf :)

[pH]armacist - Never underestimate the power of retrosynthesis. Svenskar suger på fotboll!
(Hive Bee)
10-07-02 23:02
No 365602
      dithiane synthesis  Bookmark   

There is a mysterious PDF file located at http://www.geocities.com/jolorinus666/file/meyer-vol_ib-1498_1503-dithiane.pdf containing some information about the synthesis of dithianes. Has some references as well. Also some general reaction information on the formation of 1,3-benzodithio, but nothing that would shock your knowledge.
pHarmacist: if it works, you can have one of these...

WOMAN.ZIP: Great Shareware, but be careful of viruses...
(Hive Bee)
10-08-02 00:29
No 365644
      haha  Bookmark   

LOL!!! Nice girlfriends you've got there GC_MS, they look like reasonably intelligent young ladies... tongue

[pH]armacist - Never underestimate the power of retrosynthesis. Svenskar suger på fotboll!