Oxalyl chloride is a chemical compound with the formula (COCl)2

A recent publication has described the in situ preparation of Fmoc amino acid chlorides by reaction with bis(trichloromethyl) carbonate and their use in difficult couplings [36].

O-Chlorobenzylidenemalononitrile (CAS 2698-41-1) and Bromobenzylcyanide (CAS 5798-79-8))
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The latter system is especially suitable for the cleavage of fully protected fragments to be coupled to another fragment in solution, as it eliminates the use of a carboxylic acid in the cleavage step.

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benzoic acid & its salts & esters, benzoyl peroxide & chloride, phenylactic acid & its salts & esters)
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Product name:
: 79-37-8
Molecular Formula:C2Cl2O2
Molecular Weight: 126.93
Product description:1. Used in the synthesis of benzoyl urea pesticides fluoride bell urea, kill fluid of intermediates such as urea, a short cycling and sulfonylurea herbicides, benzyl its cycling, pyrazole its cycling of intermediates, etc. 2. Oxalyl chloride is a widely used preparation carbonyl chloride and phosphoryl chloride, chlorinated paraffin and acyl cyanide acylation reagents. Oxalyl chloride is a very effective acylating reagent, can be widely used in the preparation of acyl azide, bromine rubber, carbon amide, adjacent second quinoline, azo ketones, lactones, and realize cycloaddition of ketene, intramolecular Fridel - Crafts acylation reaction. Similar to those of thionyl chloride and oxalyl chloride with the acid effect will give gas by-products, generation of chloride can be easily separated.

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Diketopiperazine formation may be circumvented in Fmoc/tBu SPPS

- by using 2-chlorotrityl chloride resin or other bulky resins such as DHPP-Resin.
- by coupling the appropriate Fmoc-dipeptide in lieu of the penultimate amino acid. In that case a risk of epimerization exists if the C-terminal amino acid of this dipeptide is not Gly or Pro.