2-(Trimethylsilyl)ethanesulfonyl (or SES) Group in Amine Protection and Activation

Abstract

group will be studied before presenting polymer-supported SES groups. SES−Cl in Synthesis Synthesis of Sulfonyl ChlorideThe free-radical addition 1 (Scheme 2) of sodium bisulfite on the double bond of vinyltrimethylsilane 1 catalyzed by tert-butyl perbenzoate provided the sulfonate salt 2 which is currently commercially available. This compound was directly transformed into sulfonyl chloride 3 (SES-Cl) by the action of phosphorus pentachloride, 1 thionyl chloride, 6 or sulfuryl chloride. 7 SES-Cl is a distillable liquid (bp ) 60°C/0.1 mmHg) which can be stored at room temperature. Protection of AminesThe formation of sulfonamide 4 is usually carried out at low temperatures by reaction of the amine with an excess of SES-Cl 3 in the presence of triethylamine (eq 2, Table 1). In the case of aromatic or heterocyclic amines, sodium hydride is instead used as a base.The simple and general synthesis of N-SES amino acids 25,26 should be noted: it starts from the corresponding salt using a temporary trimethylsilane protection on the carboxylic acid function, followed by reaction with SES-Cl (Scheme 3).

Application of a 5-endo-trig cyclisation in the total synthesis of (+)-preussin

“…To satisfy these criteria, several new protecting groups were investigated, including Boc and 4-nitrobenzenesulfonyl. The optimum group was found to be the SES protecting group developed by Weinreb et al 9,10 The N-SES protected aziridines were accessed readily from amino alcohols 10 according to the sequence outlined in Scheme 2. First, the amino alcohols 10a-c were protected as the corresponding N-SES derivatives 11a-c using SES-Cl at low temperature.…”

A Microwave‐Assisted Heck Reaction in Poly(ethylene glycol) for the Synthesis of Benzazepines

“…Yields of isolated 2a-h, 3a-h, 8a-h. amine by elimination of ethylene and sulfur dioxide. [50,51] When benzazepine 3a was subjected to classical deprotection reaction conditions (CsF, DMF), [50] the free amine 6a was obtained along with the imine 7a resulting from the oxidative elimination of the SES group.…”

2-(Trimethylsilyl)ethanesulfonamide (TMS(CH2)2SO2NH2 or SES-NH2) - A Sulfonamidation Agent With Multiple Qualities

“…2,5 On deprotection, the fluoride ion attacks the silicon atom leading to the free amine and to volatile products such as ethylene, fluorotrimethylsilane and sulfur dioxide through b-elimination. SES-NH 2 is considered as an ammonia surrogate for the palladium-catalyzed amination of aryl bromides and aryl chlorides.…”