Anúncios
Some exam samples
17 Dezembro 2018, 17:37 • Christopher David Maycock
Não consigo graver aqua os tests new em PDF. Vou tenter novamente talvez por e-mail.
CDM
Pd catalysed coupling reactions
17 Dezembro 2018, 17:30 • Christopher David Maycock
Block 2 experiments
27 Novembro 2018, 11:03 • Christopher David Maycock
The experimental protocol for the last two experiments is described below.
5-Iodo-2-aminopyridine.
To a solution of 2-aminopyridine (5 g, 0.053 mol) in glacial acetic acid (31.9 mL) at r.t.,
was added KIO3 (2.3 g, 0.011 mol) dissolved in water (6.4 mL), and I2 (5.4 g, 0.021
mol), and the reaction was stirred at 80 °C for 3 h. The mixture was poured into 5%
aqueous Na2S2O3 (100 mL) and extracted with ethyl ether (3 x 50 mL), the combined
organic layers were washed with aqueous NaOH solution until pH 7-8 and this aqueous
phase was re-extracted with ethyl ether. The final combined organic layer was dried
(K2CO3) and concentrated. After filtration and evaporation under vacuum, purification
by recrystallisation (AcOEt) gave title compound (9.12 g, 78%) as large white crystals.
M.p. 126-130OC
1H NMR (CDCl 3): δ 8.22 (1H, d, J=1.8 Hz, H-6); 7.62 (1H, dd, J=8.7 Hz, J=2.4
Hz, H-4); 6.35 (1H, d, J=8.7 Hz, H-3); 4.48 (2H, broad s, NH2).
Record the IR spectrum.
2-Chloro-5-iodopyridine.
To a solution of 2-amino-5-iodopyridine (3 g, 0.014 mol) in concentrated HCl (6.4
mL) at -5 °C, was added NaNO2 (2.4 g, 0.035 mol) dissolved in water (10.9 mL). The
temperature was allowed to rise slowly to r.t. and the reaction mixture was stirred for
1.5 h. At 0 °C aqueous NaOH solution was added until pH 7-8 (solid may be added as
before, with care) and the aqueous phase was extracted with ethyl ether (3 x 50 mL), the
combined organic layers were washed with water, and this aqueous phase was
reextracted with ethyl ether. The final combined organic layer was dried (K2CO3) and
concentrated. The residue was washed several times with hexane and this was
evaporated and not decanted, in order to remove the pink colour. No further purification
was needed, and the title compound was obtained as very light white crystals (2.44 g,
75%). M.p. 95-98OC
1H NMR (CDCl 3): δ 8.60 (1H, d, J=2.1 Hz, H-6); 7.92 (1H, dd, J=8.4 Hz, J=2.4
Hz, H-4); 6.35 (1H, d, J=8.4 Hz, H-3).
Record the IR spectrum
List of Practical experiments
9 Outubro 2018, 13:39 • Christopher David Maycock
Sintese em Química Organica 2018-2019
Practicas
Bloco 1
1. Sintese de Benzopinacol Vogel P. 528 (method A) (1 aula)
2. Sintese de 7,7-Diclorobiciclo[4.1.0]heptano Vogel P. 1110 (1 aula)
3. Sintese de 1,1’-Bi-2-naftol Vogel P. 838 (1 aula)
4. Sintese de Ciclohexeno Vogel P.491 (1 aula)
Bloco 2
5.ver folha Sintese de 2-Amino-5-iodopiridina
6.ver folha Sintese de2-Cloro-5-iodopiridina