3.3.14 Organic synthesis (A2) Flashcards
what is organic synthesis?
using reaction mechanisms to create a target molecule from a starting molecule
why do you try and keep the number of steps as low as possible for organic synthesis?
to improve the percentage yield of the final product
what could cause the yield of an individual step to be low in organic synthesis?
product left in reaction mixture each time/inefficient separation
incomplete/reversible reactions
what is the main oxidising agent used in organic chemistry?
acidified potassium dichromate (VI) (K2Cr2O7/H2SO4)
what are primary alcohols oxidised to?
aldehydes, then carboxylic acids
what are secondary alcohols oxidised to?
ketones
what are the three main reducing agents used in organic chemistry; what do they reduce?
NaBH4 sodium tetrahydridoborate (III) reduces C=O (H delta - attacks C delta +)
H2/Ni reduces C=C
Tin (Sn) / HCl reduces NO2 to NH2
what are the two main dehydrating agents used in organic synthesis?
Al2O3 (vapours passed over it)
acid-catalysed elimination by H3PO4
what does a compound being solid indicate?
long C chain or ionic
what does a compound being liquid indicate?
medium C chain or polar bonding or hydrogen bonding
what does a compound being a gas indicate?
short C chain or non-polar bonds
what does being soluble in water indicate about a compound?
suggests the compound has polar groups
what does being insoluble in water indicate about a compound?
suggests the compound has non-polar groups
what does a smoky flame when burnt suggest?
high C:H ratio, possibly aromatic
what does a non-smoky flame suggest?
low C:H ratio, not aromatic
